The LINSTOR User’s Guide
Please Read This First
This guide is intended to serve users of the software-defined storage (SDS) solution LINSTOR® as a definitive reference guide and handbook.
This guide assumes, throughout, that you are using the latest version of LINSTOR and related tools. |
This guide is organized as follows:
-
An Introduction to LINSTOR is a foundational overview of LINSTOR and provides explanations for LINSTOR concepts and terms.
-
Basic Administrative Tasks and System Setup deals with LINSTOR’s basic functionality and gives you insight into using common administrative tasks. You can also use this chapter as a step-by-step instruction guide to deploy LINSTOR with a basic, minimal setup.
-
Further LINSTOR Tasks shows a variety of advanced and important LINSTOR tasks as well as configurations, so that you can use LINSTOR in more complex ways.
-
Administering LINSTOR by GUI deals with the graphical client approach to managing LINSTOR clusters that is available to LINBIT® customers.
-
LINSTOR Integrations has chapters that deal with how to implement a LINSTOR based storage solution with various platforms and technologies, such as Kubernetes, Proxmox VE, OpenNebula, Docker, OpenStack, and others, by using the LINSTOR API.
Introduction to LINSTOR
1. An Introduction to LINSTOR
To use LINSTOR® effectively, this “Introduction to LINSTOR” chapter provides an overview of the software, explains how it works and deploys storage, and introduces and explains important concepts and terms to help your understanding.
1.1. An Overview of LINSTOR
LINSTOR is an open source configuration management system, developed by LINBIT® for storage on Linux systems. It manages LVM logical volumes, ZFS ZVOLs, or both, on a cluster of nodes. It uses DRBD® for replication between different nodes and to provide block storage devices to users and applications. Some of its features include snapshots, encryption, and caching of HDD backed data in SSDs.
1.1.1. Where LINSTOR is Used
LINSTOR was originally developed to manage DRBD resources. While you can still use LINSTOR to make managing DRBD more convenient, LINSTOR has evolved and it is often integrated with software stacks higher up to provide persistent storage more easily and more flexibly than would otherwise be possible within those stacks.
LINSTOR can be used on its own or you can integrate it with other platforms, such as Kubernetes, OpenShift, OpenNebula, OpenStack, Proxmox VE, and others. LINSTOR runs on bare-metal on-premise hardware, or you can use it within virtual machines (VMs), containers, clouds, or hybrid environments.
1.1.2. LINSTOR Supported Storage and Related Technologies
LINSTOR can work with the following storage provider and related technologies:
-
LVM and LVM thin volumes
-
ZFS and ZFS thin volumes
-
File and FileThin (loop devices)
-
Diskless
-
Exos
-
SPDK (remote)
-
Microsoft Windows Storage Spaces and thin Storage Spaces
-
EBS (target and initiator)
-
Device mapper cache (
dm-cache
) and writecache (dm-writecache
) -
bcache
-
LUKS
-
DRBD
By using LINSTOR, you can work with these technologies on their own or else in various meaningful combinations.
1.2. How LINSTOR Works
A working LINSTOR setup requires one active controller node that runs the LINSTOR
controller software as a systemd service, linstor-controller.service
. This is the LINSTOR
control plane, where the LINSTOR controller node communicates with LINSTOR satellite nodes.
The setup also requires one or more satellite nodes that run the LINSTOR satellite software as a
systemd service, linstor-satellite.service
. The LINSTOR satellite service facilitates storage and related actions on the node, for example creating storage volumes to provide data storage to users and applications. However, satellite nodes do not have to provide
physical storage to the cluster. For example, you can have diskless satellite nodes that
participate in the LINSTOR cluster for DRBD quorum purposes.
It is also possible for a node to run both the LINSTOR controller and satellite services and act in a Combined role. |
You can think of the storage technologies as implemented on LINSTOR satellite nodes, for example, DRBD replication, as the data plane. With LINSTOR, the control and data planes are separate and can function independently. This means, for example, that you can update the LINSTOR controller node or the LINSTOR controller software while your LINSTOR satellite nodes continue to provide (and replicate if using DRBD) storage to users and applications without interruption.
For convenience, a LINSTOR setup is often called a LINSTOR cluster in this guide, even though a valid LINSTOR setup can exist as an integration within another platform, such as Kubernetes.
Users can interact with LINSTOR by using either a CLI-based client or a graphical user interface (GUI). Both of these interfaces make use of the LINSTOR REST API. LINSTOR can integrate with other platforms and applications by using plugins or drivers that also make use of this API.
Communication between the LINSTOR controller and the REST API happens via TCP/IP and can be secured by using SSL/TLS.
The southbound drivers that LINSTOR uses to interface with physical storage are LVM, thinLVM and ZFS.
1.3. Installable Components
A LINSTOR setup has three installable components:
-
LINSTOR controller
-
LINSTOR satellite
-
LINSTOR user interfaces (LINSTOR client and LINBIT SDS GUI)
These installable components are either source code that you can compile, or else prebuilt packages, that you can use to install and run the software.
1.3.1. LINSTOR Controller
The linstor-controller
service relies on a database that holds all the configuration
information for the whole cluster. A node or container running the LINSTOR controller software is responsible for resource placement,
resource configuration, and orchestration of any operational processes that require a view of
the whole cluster.
Multiple controllers can be used for LINSTOR, for example, when setting up a highly available LINSTOR cluster, but only one controller can be active.
As mentioned earlier, the LINSTOR controller operates on a separate plane from the data plane that it manages. You can stop the controller service, update or reboot the controller node, and still have access to your data hosted on the LINSTOR satellite nodes. While you can still access and serve the data on your LINSTOR satellite nodes, without a running controller node, you will not be able to perform any LINSTOR status or management tasks on the satellite nodes.
1.3.2. LINSTOR Satellite
The linstor-satellite
service runs on each node where LINSTOR consumes local storage or
provides storage to services. It is stateless and receives all the information it needs from the
node or container running the LINSTOR controller service. The LINSTOR satellite service runs programs like lvcreate
and drbdadm
. It acts
like an agent on a node or in a container that carries out instructions that it receives from the LINSTOR controller node or container.
1.3.3. LINSTOR User Interfaces
When you need to interface with LINSTOR, you can send instructions to the active LINSTOR controller by using one of its user interfaces (UIs): the LINSTOR client, or the LINBIT SDS GUI.
Both of these UIs rely on the LINSTOR REST API.
LINSTOR Client
The LINSTOR client, linstor
, is a command line utility that you can use to issue commands to
the active LINSTOR controller node. These commands can be action-oriented, such as commands that
create or modify storage resources in your cluster, or they can be status commands to glean
information about the current state of your LINSTOR cluster.
You can use the LINSTOR client either by entering linstor
followed by valid commands and
arguments, or in the client’s interactive mode, by entering linstor
on its own.
You can find more information about using the LINSTOR client in the Using the LINSTOR Client section in this user’s guide.
# linstor Use "help <command>" to get help for a specific command. Available commands: - advise (adv) - backup (b) - controller (c) - drbd-proxy (proxy) - encryption (e) - error-reports (err) - exos - file (f) - help - interactive - key-value-store (kv) - list-commands (commands, list) - node (n) - node-connection (nc) - physical-storage (ps) - remote - resource (r) - resource-connection (rc) - resource-definition (rd) - resource-group (rg) - schedule (sched) - snapshot (s) - sos-report (sos) - space-reporting (spr) - storage-pool (sp) - volume (v) - volume-definition (vd) - volume-group (vg) LINSTOR ==>
LINBIT SDS Graphical User Interface
The LINBIT SDS graphical user interface (GUI) is a web-based GUI that you can use to work with LINSTOR. It can be a convenient way to navigate and get overview information about a LINSTOR cluster, or add, modify, or delete LINSTOR objects within a cluster. For example, you can add nodes, add or delete resources, or do other tasks.
You can find more information about using the GUI interface in the LINBIT SDS GUI chapter in this user’s guide.

1.4. Internal Components
The internal components of LINSTOR are abstractions of the software code that are used to describe how LINSTOR works and how you use it. Examples of internal components would be LINSTOR objects, such as resources or storage pools. Although these are abstractions, you will interact with them in a very real way as you use either the LINSTOR client or GUI to deploy and manage storage.
Along the way, this section also introduces and explains core concepts and terms that you will need to familiarize yourself with to understand how LINSTOR works and how to use it.
1.4.1. LINSTOR Objects
LINSTOR takes an object-oriented approach to software-defined storage (SDS). LINSTOR objects are the end result that LINSTOR presents to the user or application to consume or build upon.
The most commonly used LINSTOR objects are explained below and a full list of objects follows.
Resource
A resource is the LINSTOR object that represents consumable storage that is presented to applications and end users. If LINSTOR is a factory, then a resource is the finished product that it produces. Often, a resource is a DRBD replicated block device but it does not have to be. For example, a resource could be diskless to satisfy DRBD quorum requirements, or it could be an NVMe-oF or EBS initiator.
A resource has the following attributes:
-
The name of the node that the resource exists on
-
The resource definition that the resource belongs to
-
Configuration properties of the resource
Volume
A volume is the closest LINSTOR internal component to physical storage and is a subset of a resource. A resource can have multiple volumes. For example, you might want to have a database stored on slower storage than its transaction log in a MySQL cluster. To accomplish this by using LINSTOR, you could have one volume for the faster transaction log storage media and another for the slower database storage media, and have both under a single “MySQL” resource. By keeping multiple volumes under a single resource you are essentially creating a consistency group.
An attribute that you specify for a volume takes precedence over the same attribute if it is also specified “higher up” in the LINSTOR object hierarchy. This is because, again, a volume is the closest internal LINSTOR object to physical storage.
Node
A Node is a server or container that participates in a LINSTOR cluster. The node object has the following attributes:
-
Name
-
IP address
-
TCP port
-
Node type (controller, satellite, combined, auxiliary)
-
Communication type (plain or SSL/TLS)
-
Network interface type
-
Network interface name
Storage Pool
A storage pool identifies storage that is assignable to other LINSTOR objects, such as LINSTOR resources, resource definitions, or resource groups, and can be consumed by LINSTOR volumes.
A storage pool defines:
-
The storage back-end driver to use for the storage pool on the cluster node, for example, LVM, thin-provisioned LVM, ZFS, and others
-
The node that the storage pool exists on
-
The storage pool name
-
Configuration properties of the storage pool
-
Additional parameters to pass to the storage pool’s back-end driver (LVM, ZFS, and others)
A List of LINSTOR Objects
LINSTOR has the following core objects:
EbsRemote |
ResourceConnection |
SnapshotVolumeDefinition |
ExternalFile |
ResourceDefinition |
StorPool |
KeyValueStore |
ResourceGroup |
StorPoolDefinition |
LinstorRemote |
S3Remote |
Volume |
NetInterface |
Schedule |
VolumeConnection |
Node |
Snapshot |
VolumeDefinition |
NodeConnection |
SnapshotDefinition |
VolumeGroup |
1.4.2. Definition and Group Objects
While definitions and groups are also LINSTOR objects, they are a special kind. Definition and group objects can be thought of as profiles or templates. These template objects are used to create child objects that will inherit their parent object’s attributes. They might also have attributes that can affect child objects but are not attributes of the child objects themselves. These attributes could be things such as the TCP port to use for DRBD replication or the volume number that a DRBD resource should use.
Definitions
Definitions define the attributes of an object. Objects created from a definition will inherit the configuration attributes defined in the definition. A definition must be created before you can create an associated child object. For example, you must create a resource definition prior to creating the corresponding resource.
There are two LINSTOR definition objects that you can create directly, by using the LINSTOR client: resource definitions and volume definitions.
- Resource definition
-
Resource definitions can define the following attributes of a resource:
-
The resource group that the resource definition belongs to
-
The name of a resource (implicitly, by virtue of the resource definition’s name)
-
The TCP port to use for the resource’s connection, for example, when DRBD is replicating data
-
Other attributes such as a resource’s storage layers, peer slots, and external name.
-
- Volume definition
-
Volume definitions can define the following:
-
The size of the storage volume
-
The volume number of the storage volume (because a resource can have multiple volumes)
-
The metadata properties of the volume
-
The minor number to use for the DRBD device, if the volume is associated DRBD replicated storage
-
In addition to these definitions, LINSTOR has some indirect definitions: the storage pool definition, the snapshot definition, and the snapshot volume definition. LINSTOR creates these automatically when you create the respective object.
Groups
Groups are similar to definitions in that they are like profiles or templates. Where definitions apply to LINSTOR object instances, groups apply to object definitions. As the name implies, a group can apply to multiple object definitions, just as a definition can apply to multiple object instances. For example, you can have a resource group that defines resource attributes for a frequently needed storage use case. You can then use the resource group to easily spawn (create) multiple resources that need to have those attributes, without having to specify the attributes every time you create a resource.
- Resource group
-
A resource group is a parent object of a resource definition where all property changes made on a resource group will be inherited by its resource definition children[1]. The resource group also stores settings for automatic placement rules and can spawn a resource definition depending on the stored rules.
A resource group defines characteristics of its resource definition child objects. A resource spawned from the resource group, or created from a resource definition that belongs to the resource group, will be a “grandchild” object of a resource group and the “child” of a resource definition. Every resource definition that you create will be a member of the default LINSTOR resource group,
DfltRscGrp
, unless you specify another resource group when creating the resource definition.Changes to a resource group will be applied to all resources or resource definitions that were created from the resource group, retroactively, unless the same characteristic has been set on a child object, for example, a resource definition or resource that was created from the resource group.
All of this makes using resource groups a powerful tool to efficiently manage a large number of storage resources. Rather than creating or modifying individual resources, you can simply configure a resource group parent, and all the child resource objects will receive the configuration.
- Volume group
-
Similarly, volume groups are like profiles or templates for volume definitions. A volume group must always reference a specific resource group. In addition, a volume group can define a volume number, and a “gross” volume size.
1.5. LINSTOR Object Hierarchy
As alluded to in previous subsections of this chapter, there is a concept of hierarchy among LINSTOR objects. Depending on the context, this can be described either as a parent-child relationship, or else as a higher-lower relationship where lower means closer to the physical storage layer[2].
A child object will inherit attributes that are defined on its parent objects, so long as the same attributes are not already defined on the child object. Similarly, a lower object will receive attributes that are set on higher objects, so long as the same attributes are not already defined on the lower object.
1.5.1. General Rules for Object Hierarchy in LINSTOR
The following are some general rules for object hierarchy in LINSTOR:
-
A LINSTOR object can only receive or inherit attributes that can be set on that object.
-
Lower objects receive attributes set on higher objects.
-
An attribute set on a lower object takes precedence over the same attribute set on higher objects.
-
Child objects inherit attributes set on parent objects.
-
An attribute set on a child object takes precedence over the same attribute set on parent objects.
1.5.2. Using Diagrams to Show Relationships Between LINSTOR Objects
This section uses diagrams to represent the hierarchical relationships between some of the most frequently used LINSTOR objects. Because of the number of LINSTOR objects and their interconnectedness, multiple diagrams are shown first rather than a single diagram, to simplify the conceptualization.
The next diagram shows the relationships between LINSTOR group objects on a single satellite node.
While the two preceding diagrams show higher-lower relationships between common LINSTOR objects, you can also think of some LINSTOR objects as having parent-child relationships. The next diagram introduces this kind of relationship between LINSTOR objects by using a storage pool definition (parent object) and a storage pool (child object) as an example. A parent object can have multiple child objects, as shown in the following diagram.
Having introduced the concept of parent-child relationships in a conceptual diagram, the next diagram is a modified version of the second diagram with some of those relationships added for groups and definitions. This modified diagram also incorporates some of the higher-lower relationships that were shown in the first diagram.
The next diagram synthesizes the relationship concepts of the preceding diagrams while also introducing new LINSTOR objects related to snapshots and connections. With the many objects and criss-crossing lines, the reason for building up to this diagram should be apparent.
Even with its seeming complexity, the preceding diagram is still a simplification and not an all-encompassing representation of the possible relationships between LINSTOR objects. As listed earlier, there are more LINSTOR objects than are shown in the diagram[3].
The good news is that you do not need to memorize the preceding diagram to work with LINSTOR. It could be useful to refer to though if you are trying to troubleshoot attributes that you have set on LINSTOR objects and their inheritance and effects on other LINSTOR objects in your cluster.
Administering LINSTOR
2. Basic Administrative Tasks and System Setup
This is a how-to style chapter that covers basic LINSTOR administrative tasks, including installing LINSTOR and how to get started using LINSTOR.
2.1. Before Installing LINSTOR
Before you install LINSTOR, there are a few things that you should be aware of that might affect how you install LINSTOR.
2.1.1. Packages
LINSTOR is packaged in both the RPM and the DEB variants:
-
linstor-client contains the command line client program. It depends on Python which is usually already installed. In RHEL 8 systems you will need to symlink
python
. -
linstor-controller and linstor-satellite Both contain systemd unit files for the services. They depend on Java runtime environment (JRE) version 1.8 (headless) or higher.
For further details about these packages see the Installable Components section above.
If you have a LINBIT® support subscription, you will have access to certified binaries through LINBIT customer-only repositories. |
2.1.2. FIPS Compliance
This standard shall be used in designing and implementing cryptographic modules…
You can configure LINSTOR to encrypt storage volumes, by using LUKS (dm-crypt
), as detailed in
the Encrypted Volumes section of this user’s guide. Refer to
the LUKS and dm-crypt
projects for FIPS compliance status.
You can also configure LINSTOR to encrypt communication traffic between a LINSTOR satellite and a LINSTOR controller, by using SSL/TLS, as detailed in the Secure Satellite Connections section of this user’s guide.
LINSTOR can also interface with Self-Encrypting Drives (SEDs) and you can use LINSTOR to initialize an SED drive. LINSTOR stores the drive’s password as a property that applies to the storage pool associated with the drive. LINSTOR encrypts the SED drive password by using the LINSTOR master passphrase that you must create first.
By default, LINSTOR uses the following cryptographic algorithms:
-
HMAC-SHA2-512
-
PBKDF2
-
AES-128
A FIPS compliant version of LINSTOR is available for the use cases mentioned in this section. If you or your organization require FIPS compliance at this level, please contact [email protected] for details.
2.2. Installing LINSTOR
If you want to use LINSTOR in containers, skip this section and use the Containers section below for the installation. |
2.2.1. Installing a Volume Manager
To use LINSTOR to create storage volumes, you will need to install a volume manager, either LVM or ZFS, if one is not already installed on your system.
2.2.2. Using a Script to Manage LINBIT Cluster Nodes
If you are a LINBIT customer, you can download a LINBIT created helper script and run it on your nodes to:
-
Register a cluster node with LINBIT.
-
Join a node to an existing LINBIT cluster.
-
Enable LINBIT package repositories on your node.
Enabling LINBIT package repositories will give you access to LINBIT software packages, DRBD kernel modules, and other related software such as cluster managers and OCF scripts. You can then use a package manager to fetch, install, and manage updating installed packages.
Downloading the LINBIT Manage Node Script
To register your cluster nodes with LINBIT, and configure LINBIT’s repositories, first download and then run the manage node helper script by entering the following commands on all cluster nodes:
# curl -O https://my.linbit.com/linbit-manage-node.py # chmod +x ./linbit-manage-node.py # ./linbit-manage-node.py
You must run the script as the root user.
|
The script will prompt you for your LINBIT customer portal username and password. After entering your credentials, the script will list cluster nodes associated with your account (none at first).
Enabling LINBIT Package Repositories
After you specify which cluster to register the node with, have the script write the
registration data to a JSON file when prompted. Next, the script will show you a list of LINBIT
repositories that you can enable or disable. You can find LINSTOR and other related packages
in the drbd-9
repository. In most cases, unless you have a need to be on a different DRBD
version branch, you should enable at least this repository.
Final Tasks Within Manage Nodes Script
After you have finished making your repositories selection, you can write the configuration to a file by following the script’s prompting. Next, be sure to answer yes to the question about installing LINBIT’s public signing key to your node’s keyring.
Before it closes, the script will show a message that suggests different packages that you can install for different use cases.
On DEB based systems you can install a precompiled DRBD kernel module package,
drbd-module-$(uname -r) , or a source version of the kernel module, drbd-dkms . Install one
or the other package but not both.
|
2.2.3. Using a Package Manager to Install LINSTOR
After registering your node and enabling the drbd-9
LINBIT package repository, you can use a
DEB, RPM, or YaST2 based package manager to install LINSTOR and related components.
If you are using a DEB based package manager, refresh your package repositories list
by entering: apt update , before proceeding.
|
Installing DRBD Packages for Replicated LINSTOR Storage
If you will be using LINSTOR without DRBD, you can skip installing theses packages. |
If you want to be able to use LINSTOR to create DRBD replicated storage, you will need to install the required DRBD packages. Depending on the Linux distribution that you are running on your node, install the DRBD-related packages that the helper script suggested. If you need to review the script’s suggested packages and installation commands, you can enter:
# ./linbit-manage-node.py --hints
Installing LINSTOR Packages
To install LINSTOR on a controller node, use your package manager to install the
linbit-sds-controller
package.
To install LINSTOR on a satellite node, use your package manager to install the
linbit-sds-satellite
package.
Install both packages if your node will be both a satellite and controller (Combined role).
2.2.4. Installing LINSTOR from Source Code
The LINSTOR project’s GitHub page is here: https://github.com/LINBIT/linstor-server.
LINBIT also has downloadable archived files of source code for LINSTOR, DRBD, and more, available here: https://linbit.com/linbit-software-download-page-for-linstor-and-drbd-linux-driver/.
2.3. Upgrading LINSTOR
LINSTOR doesn’t support rolling upgrades. Controller and satellites must have the same version, otherwise
the controller will discard the satellite with a VERSION_MISMATCH
.
But this isn’t a problem, as the satellite won’t do any actions as long it isn’t connected to a controller
and DRBD will not be disrupted by any means.
If you are using the embedded default H2 database and the linstor-controller package is upgraded an automatic
backup file of the database will be created in the default /var/lib/linstor
directory.
This file is a good restore point if for any reason a linstor-controller database migration should fail,
then it is recommended to report the error to LINBIT and restore the old database file and roll back to your previous
controller version.
If you use any external database or etcd, it is recommended to do a manual backup of your current database to have a restore point.
First, upgrade the linstor-controller
and linstor-client
packages on your controller host and then restart the linstor-controller
.
The controller should start and all of its clients should show OFFLINE(VERSION_MISMATCH)
.
After that you can continue upgrading the linstor-satellite
package on all satellite nodes and restart them, after a short reconnection time
they should all show ONLINE
again and your upgrade is finished.
2.4. Containers
LINSTOR and related software are also available as containers. The base images are available
in LINBIT’s container registry, drbd.io
.
LINBIT’s container image repository (http://drbd.io) is only available to LINBIT customers or through LINBIT customer trial accounts. Contact LINBIT for information on pricing or to begin a trial. Alternatively, you may use LINSTOR SDS’ upstream project named Piraeus, without being a LINBIT customer. |
To access the images, you first have to login to the registry using your LINBIT Customer Portal credentials.
# docker login drbd.io
The containers available in this repository are:
-
drbd.io/drbd9-rhel8
-
drbd.io/drbd9-rhel7
-
drbd.io/drbd9-sles15sp1
-
drbd.io/drbd9-bionic
-
drbd.io/drbd9-focal
-
drbd.io/linstor-csi
-
drbd.io/linstor-controller
-
drbd.io/linstor-satellite
-
drbd.io/linstor-client
An up-to-date list of available images with versions can be retrieved by opening http://drbd.io in your
browser. Be sure to browse the image repository through HTTP, although the registry’s images themselves are pulled through HTTPS, using the associated docker pull
command.
To load the kernel module, needed only for LINSTOR satellites, you’ll need to
run a drbd9-$dist
container in privileged mode. The kernel module containers
either retrieve an official LINBIT package from a customer repository, use
shipped packages, or they try to build the kernel modules from source. If you
intend to build from source, you need to have the according kernel headers
(e.g., kernel-devel
) installed on the host. There are four ways to execute such
a module load container:
-
Building from shipped source
-
Using a shipped/pre-built kernel module
-
Specifying a LINBIT node hash and a distribution.
-
Bind-mounting an existing repository configuration.
Example building from shipped source (RHEL based):
# docker run -it --rm --privileged -v /lib/modules:/lib/modules \ -v /usr/src:/usr/src:ro \ drbd.io/drbd9-rhel7
Example using a module shipped with the container, which is enabled by not bind-mounting /usr/src
:
# docker run -it --rm --privileged -v /lib/modules:/lib/modules \ drbd.io/drbd9-rhel8
Example using a hash and a distribution (rarely used):
# docker run -it --rm --privileged -v /lib/modules:/lib/modules \ -e LB_DIST=rhel7.7 -e LB_HASH=ThisIsMyNodeHash \ drbd.io/drbd9-rhel7
Example using an existing repo configuration (rarely used):
# docker run -it --rm --privileged -v /lib/modules:/lib/modules \ -v /etc/yum.repos.d/linbit.repo:/etc/yum.repos.d/linbit.repo:ro \ drbd.io/drbd9-rhel7
In both cases (hash + distribution, as well as bind-mounting a repo) the hash or repo configuration has to be from a node that has a special property set. Feel free to contact our support, and we will set this property. |
For now (i.e., pre DRBD 9 version “9.0.17”), you must use the containerized DRBD kernel module,
as opposed to loading a kernel module onto the host system. If you
intend to use the containers you should not install the DRBD kernel
module on your host systems. For DRBD version 9.0.17 or greater, you can install the kernel module as usual on
the host system, but you need to load the module with the usermode_helper=disabled parameter
(e.g., modprobe drbd usermode_helper=disabled ).
|
Then run the LINSTOR satellite container, also privileged, as a daemon:
# docker run -d --name=linstor-satellite --net=host -v /dev:/dev \ --privileged drbd.io/linstor-satellite
net=host is required for the containerized drbd-utils to be
able to communicate with the host-kernel through Netlink.
|
To run the LINSTOR controller container as a daemon, mapping TCP port 3370
on the host to the container, enter the following command:
# docker run -d --name=linstor-controller -p 3370:3370 drbd.io/linstor-controller
To interact with the containerized LINSTOR cluster, you can either use a LINSTOR client installed on a system using repository packages, or using the containerized LINSTOR client. To use the LINSTOR client container:
# docker run -it --rm -e LS_CONTROLLERS=<controller-host-IP-address> \ drbd.io/linstor-client node list
From this point you would use the LINSTOR client to initialize your cluster and begin creating resources using the typical LINSTOR patterns.
To stop and remove a daemonized container and image:
# docker stop linstor-controller # docker rm linstor-controller
2.5. Initializing Your Cluster
We assume that the following steps are accomplished on all cluster nodes:
-
The DRBD9 kernel module is installed and loaded.
-
drbd-utils
are installed. -
LVM
tools are installed. -
linstor-controller
and/orlinstor-satellite
its dependencies are installed. -
The
linstor-client
is installed on thelinstor-controller
node.
Enable and also start the linstor-controller
service on the host where it has been installed:
# systemctl enable --now linstor-controller
2.6. Using the LINSTOR Client
Whenever you run the LINSTOR command line client, it needs to know where your
linstor-controller runs. If you do not specify it, it will try to reach a locally
running linstor-controller listening on IP 127.0.0.1
port 3370
. Therefore we
will use the linstor-client
on the same host as the linstor-controller
.
The linstor-satellite requires TCP ports 3366 and 3367. The linstor-controller
requires TCP port 3370. Verify that you have this port allowed on your firewall.
|
# linstor node list
Output from this command should show you an empty list and not an error message.
You can use the linstor
command on any other machine, but then you need
to tell the client how to find the linstor-controller. As shown, this can be
specified as a command line option, an environment variable, or in a global
file:
# linstor --controllers=alice node list # LS_CONTROLLERS=alice linstor node list
Alternatively you can create the /etc/linstor/linstor-client.conf
file and populate it like below.
[global] controllers=alice
If you have multiple linstor-controllers configured you can simply specify them all in a comma separated list. The linstor-client will simply try them in the order listed.
The linstor-client commands can also be used in a much faster
and convenient way by only writing the starting letters of the parameters
e.g.: linstor node list → linstor n l
|
2.7. Adding Nodes to Your Cluster
The next step is to add nodes to your LINSTOR cluster.
# linstor node create bravo 10.43.70.3
If the IP is omitted, the client will try to resolve the given node-name as host-name by itself.
LINSTOR will automatically detect the node’s local uname -n
which is
later used for the DRBD-resource.
When you use linstor node list
you will see that the new node
is marked as offline. Now start and enable the linstor-satellite on that node
so that the service comes up on reboot as well:
# systemctl enable --now linstor-satellite
You can also use systemctl start linstor-satellite
if you are sure that the service is already enabled as default and comes up on
reboot.
About 10 seconds later you will see the status in linstor node list
becoming online. Of course the satellite process may be started before
the controller knows about the existence of the satellite node.
In case the node which hosts your controller should also contribute storage to the LINSTOR cluster, you have to add it as a node and start the linstor-satellite as well. |
If you want to have other services wait until the linstor-satellite had a chance
to create the necessary devices (that is, after a boot), you can update the
corresponding .service
file and change Type=simple
to Type=notify
.
This will cause the satellite to delay sending the READY=1
message to systemd
until the controller connects, sends all required data to the satellite and the
satellite at least tried once to get the devices up and running.
2.8. Storage Pools
StoragePools identify storage in the context of LINSTOR. To group storage pools from multiple nodes, simply use the same name on each node. For example, one valid approach is to give all SSDs one name and all HDDs another.
2.8.1. Creating Storage Pools
On each host contributing storage, you need to create either an LVM volume group (VG) or a ZFS zPool. The VGs and zPools identified with one LINSTOR storage pool name may have different VG or zPool names on the hosts, but do yourself a favor, for coherency, use the same VG or zPool name on all nodes.
# vgcreate vg_ssd /dev/nvme0n1 /dev/nvme1n1 [...]
After creating a volume group on each of your nodes, you can create a storage pool that is backed by the volume group on each of your nodes, by entering the following commands:
# linstor storage-pool create lvm alpha pool_ssd vg_ssd # linstor storage-pool create lvm bravo pool_ssd vg_ssd
To list your storage pools you can enter:
# linstor storage-pool list
or using LINSTOR abbreviated notation:
# linstor sp l
2.8.2. Using Storage Pools To Confine Failure Domains to a Single Back-end Device
In clusters where you have only one kind of storage and the capability to hot swap storage devices, you may choose a model where you create one storage pool per physical backing device. The advantage of this model is to confine failure domains to a single storage device.
2.8.3. Sharing Storage Pools with Multiple Nodes
Both the Exos and LVM2 storage providers offer the option of multiple server nodes directly connected
to the storage array and drives. With LVM2 the external locking service (lvmlockd) manages volume groups
created with the –shared options with vgcreate. The --shared-space
can be used when configuring a LINSTOR
pool to use the same LVM2 volume group accessible by
two or more nodes. The example below shows using the LVM2
volume group UUID as the shared space identifier for a pool accessible by nodes alpha and bravo:
# linstor storage-pool create lvm --external-locking \ --shared-space O1btSy-UO1n-lOAo-4umW-ETZM-sxQD-qT4V87 \ alpha pool_ssd shared_vg_ssd # linstor storage-pool create lvm --external-locking \ --shared-space O1btSy-UO1n-lOAo-4umW-ETZM-sxQD-qT4V87 \ bravo pool_ssd shared_vg_ssd
Exos pools will use the Exos pool serial number by default for the shared-space identifier.
2.8.4. Creating Storage Pools by Using the Physical Storage Command
Since linstor-server 1.5.2 and a recent linstor-client, LINSTOR can create LVM/ZFS pools on a satellite for you. The linstor-client has the following commands to list possible disks and create storage pools, but such LVM/ZFS pools are not managed by LINSTOR and there is no delete command, so such action must be done manually on the nodes.
# linstor physical-storage list
Will give you a list of available disks grouped by size and rotational(SSD/Magnetic Disk).
It will only show disks that pass the following filters:
-
The device size must be greater than 1GiB.
-
The device is a root device (not having children), for example,
/dev/vda
,/dev/sda
. -
The device does not have any file system or other
blkid
marker (wipefs -a
might be needed). -
The device is not a DRBD device.
With the create-device-pool
command you can create a LVM pool on a disk and also directly
add it as a storage pool in LINSTOR.
# linstor physical-storage create-device-pool --pool-name lv_my_pool \ LVMTHIN node_alpha /dev/vdc --storage-pool newpool
If the --storage-pool
option was provided, LINSTOR will create a storage pool with the given name.
For more options and exact command usage please check the linstor-client help.
2.9. Using Resource Groups to Deploy LINSTOR Provisioned Volumes
Using resource groups to define how you would like your resources provisioned should be considered the de facto method for deploying volumes provisioned by LINSTOR. Chapters that follow which describe creating each resource from a resource-definition and volume-definition should only be used in special scenarios.
Even if you choose not to create and use resource-groups in your LINSTOR cluster, all resources created from resource-definitions and volume-definitions will exist in the ‘DfltRscGrp’ resource-group. |
A simple pattern for deploying resources using resource groups would look like this:
# linstor resource-group create my_ssd_group --storage-pool pool_ssd --place-count 2 # linstor volume-group create my_ssd_group # linstor resource-group spawn-resources my_ssd_group my_ssd_res 20G
The commands above would result in a resource named ‘my_ssd_res’ with a 20GB volume replicated twice being automatically provisioned from nodes who participate in the storage pool named ‘pool_ssd’.
A more useful pattern could be to create a resource group with settings you’ve determined are optimal for your use case. Perhaps you have to run nightly online verifications of your volumes’ consistency, in that case, you could create a resource group with the ‘verify-alg’ of your choice already set so that resources spawned from the group are pre-configured with ‘verify-alg’ set:
# linstor resource-group create my_verify_group --storage-pool pool_ssd --place-count 2 # linstor resource-group drbd-options --verify-alg crc32c my_verify_group # linstor volume-group create my_verify_group # for i in {00..19}; do linstor resource-group spawn-resources my_verify_group res$i 10G done
The commands above result in twenty 10GiB resources being created each with the ‘crc32c’ ‘verify-alg’ pre-configured.
You can tune the settings of individual resources or volumes spawned from resource groups by setting options on the respective resource-definition or volume-definition. For example, if ‘res11’ from the example above is used by a very active database receiving many small random writes, you might want to increase the ‘al-extents’ for that specific resource:
# linstor resource-definition drbd-options --al-extents 6007 res11
If you configure a setting in a resource-definition that is already configured on the resource-group it was spawned from, the value set in the resource-definition will override the value set on the parent resource-group. For example, if the same ‘res11’ was required to use the slower but more secure ‘sha256’ hash algorithm in its verifications, setting the ‘verify-alg’ on the resource-definition for ‘res11’ would override the value set on the resource-group:
# linstor resource-definition drbd-options --verify-alg sha256 res11
A guiding rule for the hierarchy in which settings are inherited is that the value “closer” to the resource or volume wins: volume-definition settings take precedence over volume-group settings, and resource-definition settings take precedence over resource-group settings. |
2.11. Creating and Deploying Resources and Volumes
You can use the LINSTOR create
command to create various LINSTOR objects, such as resource
definitions, volume definitions, and resources. Some of these commands are shown below.
In the following example scenario, assume that you have a goal of creating a resource named ‘backups’ with a size of ‘500GiB’ that is replicated among three cluster nodes.
First, create a new resource definition:
# linstor resource-definition create backups
Second, create a new volume definition within that resource definition:
# linstor volume-definition create backups 500G
If you want to resize (grow or shrink) the volume definition you can do that by specifying a new
size with the set-size
command:
# linstor volume-definition set-size backups 0 100G
The size of a volume definition can only be decreased if it has no associated resource. However, you can freely increase the size of a volume definition, even one having a deployed resource. |
The parameter 0
is the number of the volume in the resource backups
. You have to provide this parameter
because resources can have multiple volumes that are identified by a so-called volume number. You can find this number
by listing the volume definitions (linstor vd l
). The list table will show volume numbers for
the listed resources.
So far you have only created definition objects in LINSTOR’s database. However, not a single logical volume (LV) has been created on the satellite nodes. Now you have the choice of delegating the task of deploying resources to LINSTOR or else doing it yourself.
2.11.1. Manually Placing Resources
With the resource create
command you may assign a resource definition
to named nodes explicitly.
# linstor resource create alpha backups --storage-pool pool_hdd # linstor resource create bravo backups --storage-pool pool_hdd # linstor resource create charlie backups --storage-pool pool_hdd
2.11.2. Automatically Placing Resources
It is possible to have LINSTOR select nodes and storage pools to deploy a resource to, by using
the linstor resource create --auto-place
or linstor resource-definition auto-place
commmands. This section will use the resource create --auto-place
command in examples.
However, you can use either command to produce the same results.
LINSTOR’s resource-group create command does not have an --auto-place option, because
the command does not deploy resources; it only creates a template from which you can later
deploy (spawn) resources. However, you can use the arguments described in this section that
accompany the --auto-place option with the resource-group create command. When used this
way, when you spawn a resource from a resource group, LINSTOR will deploy the resource as if you
had used the resource create --auto-place command.
|
If the nodes (or storage pools) in your cluster cannot fulfill the constraints of
your --auto-place command arguments, then LINSTOR will reject your command with an error
message.
|
In the following example, the value after the --auto-place
option tells LINSTOR how many
replicas you want to have. The --storage-pool
option should be obvious.
# linstor resource create backups --auto-place 3 --storage-pool pool_hdd
Maybe not so obvious is that you may omit the --storage-pool
option, then
LINSTOR may select a storage pool on its own. The selection follows these rules:
-
Ignore all nodes and storage pools the current user has no access to
-
Ignore all diskless storage pools
-
Ignore all storage pools not having enough free space
The remaining storage pools will be rated by different strategies. LINSTOR has currently three strategies:
-
MaxFreeSpace
: This strategy maps the rating 1:1 to the remaining free space of the storage pool. However, this strategy only considers the actually allocated space (in case of thin-provisioned storage pool this might grow with time without creating new resources) -
MinReservedSpace
: Unlike the “MaxFreeSpace”, this strategy considers the reserved space. That is the space that a thin volume can grow to before reaching its limit. The sum of reserved spaces might exceed the storage pool’s capacity, which is as overprovisioning. -
MinRscCount
: Simply the count of resources already deployed in a given storage pool -
MaxThroughput
: For this strategy, the storage pool’sAutoplacer/MaxThroughput
property is the base of the score, or 0 if the property is not present. Every Volume deployed in the given storage pool will subtract its definedsys/fs/blkio_throttle_read
andsys/fs/blkio_throttle_write
property- value from the storage pool’s max throughput. The resulting score might be negative.
The scores of the strategies will be normalized, weighted and summed up, where the scores of minimizing strategies will be converted first to allow an overall maximization of the resulting score.
The weights of the strategies can be configured with the following command:
linstor controller set-property Autoplacer/Weights/$name_of_the_strategy $weight
The strategy names are listed above and the weight can be an arbitrary decimal.
To keep the behavior of the Autoplacer compatible with previous LINSTOR versions, all
strategies have a default-weight of 0, except the MaxFreeSpace which has a weight of 1.
|
Neither 0 nor a negative score will prevent a storage pool from getting selected. A storage pool with these scores will just be considered later. |
Finally, LINSTOR tries to find the best matching group of storage pools meeting all
requirements. This step also considers other auto-placement restrictions such as
--replicas-on-same
, --replicas-on-different
, --do-not-place-with
,
--do-not-place-with-regex
, --layer-list
, and --providers
.
Avoiding Colocating Resources When Automatically Placing a Resource
The --do-not-place-with <resource_name_to_avoid>
argument specifies that LINSTOR should try to
avoid deploying the resource on nodes that already have the specified, resource_name_to_avoid
resource deployed.
By using the --do-not-place-with-regex <regular_expression>
argument, you can specify that
LINSTOR should try to avoid placing the resource on nodes that already have a resource deployed
whose name matches the regular expression that you provide with the argument. In this way, you
can specify multiple resources to try to avoid placing your resource with.
Constraining Automatic Resource Placement by Using Auxiliary Node Properties
You can constrain automatic resource placement to place (or avoid placing) a resource with nodes having a specified auxiliary node property.
This ability can be particularly useful if you are trying to constrain resource placement within Kubernetes environments that use LINSTOR managed storage. For example, you might set an auxiliary node property that corresponds to a Kubernetes label. See the “replicasOnSame” section within the “LINSTOR Volumes in Kubernetes” LINSTOR User’s Guide chapter for more details about this use case. |
The arguments, --replicas-on-same
and --replicas-on-different
expect the
name of a property within the Aux/
namespace.
The following example shows setting an auxiliary node property, testProperty
, on three LINSTOR
satellite nodes. Next, you create a resource group, testRscGrp
, with a place count of two and
a constraint to place spawned resources on nodes that have a testProperty
value of 1
. After
creating a volume group, you can spawn a resource from the resource group. For simplicity,
output from the following commands is not shown.
# for i in {0,2}; do linstor node set-property --aux node-$i testProperty 1; done # linstor node set-property --aux node-1 testProperty 0 # linstor resource-group create testRscGrp --place-count 2 --replicas-on-same testProperty=1 # linstor volume-group create testRscGrp # linstor resource-group spawn-resources testRscGrp testResource 100M
You can verify the placement of the spawned resource by using the following command:
# linstor resource list +-------------------------------------------------------------------------------------+ | ResourceName | Node | Port | Usage | Conns | State | CreatedOn | |=====================================================================================| | testResource | node-0 | 7000 | Unused | Ok | UpToDate | 2022-07-27 16:14:16 | | testResource | node-2 | 7000 | Unused | Ok | UpToDate | 2022-07-27 16:14:16 | +-------------------------------------------------------------------------------------+
Because of the --replicas-on-same
constraint, LINSTOR did not place the spawned resource on
satellite node node-1
, because the value of its auxiliary node property, testProperty
was
0
and not 1
.
You can verify the node properties of node-1
, by using the list-properties
command:
# linstor node list-properties node-1 +----------------------------+ | Key | Value | |============================| | Aux/testProperty | 0 | | CurStltConnName | default | | NodeUname | node-1 | +----------------------------+
Using Auto-place to Extend Existing Resource Deployments
Besides specifying a positive integer for the --auto-place
value for the number of replicas of
your resource to place, you can also specify a value of +1
, should you want to extend existing
resource deployments. By using this value, LINSTOR will create an additional replica, no matter
what the --place-count
is configured for on the corresponding resource group that the resource
was created from.
For example, you can use the +1
auto-place value to deploy an additional replica of the
testResource
resource used in the previous example. You will first need to set the auxiliary
node property, testProperty
to 1
on node-1
. Otherwise, LINSTOR will not be able to deploy
the replica because of the previously configured --replicas-on-same
constraint. For
simplicity, not all output from the commands below is shown.
# linstor node set-property --aux node-1 testProperty 1 # linstor resource create --auto-place +1 testResource # linstor resource list +----+ | ResourceName | Node | Port | Usage | Conns | State | CreatedOn | |=====================================================================================| | testResource | node-0 | 7000 | Unused | Ok | UpToDate | 2022-07-27 16:14:16 | | testResource | node-1 | 7000 | Unused | Ok | UpToDate | 2022-07-28 19:27:30 | | testResource | node-2 | 7000 | Unused | Ok | UpToDate | 2022-07-27 16:14:16 | +-------------------------------------------------------------------------------------+
The +1 value is not valid for the resource-group create --place-count command. This
is because the command does not deploy resources, it only creates templates from which to deploy
them later.
|
Constraining Automatic Resource Placement by LINSTOR Layers or Storage Pool Providers
You can specify the --layer-list
or --providers
arguments, followed by a comma-separated
values (CSV) list of LINSTOR layers or storage pool providers, to influence where LINSTOR places
your resource. The possible layers and storage pool providers that you can specify in your CSV
list can be shown by using the --help
option with the --auto-place
option. A CSV list of
layers would constrain automatic resource placement for your specified resource to nodes that
have storage that conformed with your list. For example, given an existing resource definition
named my_luks_resource
, consider the following command:
# linstor resource create my_luks_resource --auto-place 3 --layer-list drbd,luks
This command would create a resource deployed across three nodes having storage pools backed by a DRBD layer backed by a LUKS layer (and implicitly backed by a “storage” layer). The order of layers that you specify in your CSV list is “top-down”, where a layer on the left in the list is above a layer on its right.
The --providers
argument can be used to constrain automatic resource placement to only storage
pools that match those in a specified CSV list. You can use this argument to have explicit
control over which storage pools will back your deployed resource. If for example, you had a
mixed environment of ZFS
, LVM
, and LVM_THIN
storage pools in your cluster, by using the
--providers LVM,LVM_THIN
argument, you can specify that a resource only gets backed by either
an LVM
or LVM_THIN
storage pool, when using the --auto-place
option.
The --providers argument’s CSV list does not specify an order of priority for the list
elements. Instead, LINSTOR will use factors like additional --auto-place constraints,
available free space, and LINSTOR’s storage pool selection strategies that were previously
described, when placing a resource.
|
2.12. Deleting Resources, Resource Definitions, and Resource Groups
You can delete LINSTOR resources, resource definitions, and resource groups by using the
delete
command after the LINSTOR object that you want to delete. Depending on which object you
delete, there will be different implications for your LINSTOR cluster and other associated
LINSTOR objects.
2.12.1. Deleting a Resource Definition
You can delete a resource definition by using the command:
# linstor resource-definition delete <resource_definition_name>
This will remove the named resource definition from the entire LINSTOR cluster. The resource is removed from all nodes and the resource entry is marked for removal from LINSTOR’s database tables. After LINSTOR has removed the resource from all the nodes, the resource entry is removed from LINSTOR’s database tables.
If your resource definition has existing snapshots, you will not be able to delete the resource definition until you delete its snapshots. See the Removing a Snapshot section in this guide. |
2.12.2. Deleting a Resource
You can delete a resource using the command:
# linstor resource delete <node_name> <resource_name>
Unlike deleting a resource definition, this command will only delete a LINSTOR resource from the node (or nodes) that you specify. The resource is removed from the node and the resource entry is marked for removal from LINSTOR’s database tables. After LINSTOR has removed the resource from the node, the resource entry is removed from LINSTOR’s database tables.
Deleting a LINSTOR resource may have implications for a cluster, beyond just removing the resource. For example, if the resource is backed by a DRBD layer, removing a resource from one node in a three node cluster could also remove certain quorum related DRBD options, if any existed for the resource. After removing such a resource from a node in a three node cluster, the resource would no longer have quorum as it would now only be deployed on two nodes in the three node cluster.
After running a linstor resource delete
command to remove a resource from a single node, you
might see informational messages such as:
INFO: Resource-definition property 'DrbdOptions/Resource/quorum' was removed as there are not enough resources for quorum INFO: Resource-definition property 'DrbdOptions/Resource/on-no-quorum' was removed as there are not enough resources for quorum
Also unlike deleting a resource definition, you can delete a resource while there are existing snapshots of the resource’s storage pool. Any existing snapshots for the resource’s storage pool will persist.
2.12.3. Deleting a Resource Group
You can delete a resource group by using the command:
# linstor resource-group delete <resource_group_name>
As you might expect, this command deletes the named resource group. You can only delete a resource group if it has no associated resource definitions, otherwise LINSTOR will present an error message, such as:
ERROR: Description: Cannot delete resource group 'my_rg' because it has existing resource definitions.
To resolve this error so that you can delete the resource group, you can either delete the associated resource definitions, or your can move the resource definitions to another (existing) resource group:
# linstor resource-definition modify <resource_definition_name> \ --resource-group <another_resource_group_name>
You can find which resource definitions are associated with your resource group by entering the following command:
# linstor resource-definition list
2.13. Backup and Restore Database
Since version 1.24.0, LINSTOR has a tool that you can use to export and import a LINSTOR database.
This tool has an executable file called /usr/share/linstor-server/bin/linstor-database
. This executable
has two subcommands, export-db
and import-db
. Both subcommands accept an optional --config-directory
argument that you can use to specify the directory containing the linstor.toml
configuration file.
To ensure a consistent database backup, take the controller offline by stopping the controller service as shown in the commands below, before creating a backup of the LINSTOR database. |
2.13.1. Backing Up the Database
To backup the LINSTOR database to a new file named db_export
in your home directory, enter the
following commands:
# systemctl stop linstor-controller # /usr/share/linstor-server/bin/linstor-database export-db ~/db_export # systemctl start linstor-controller
You can use the --config-directory argument with the linstor-database utility to specify a
LINSTOR configuration directory if needed. If you omit this argument, the utility uses the
/etc/linstor directory by default.
|
After backing up the database, you can copy the backup file to a safe place.
# cp ~/db_export <somewhere safe>
The resulting database backup is a plain JSON document, containing not just the actual data, but also some metadata about when the backup was created, from which database, and other information.
2.13.2. Restoring the Database From a Backup
Restoring the database from a previously made backup is similar to export-db
from the
previous section.
For example, to restore the previously made backup from the db_export
file, enter the following
commands:
# systemctl stop linstor-controller # /usr/share/linstor-server/bin/linstor-database import-db ~/db_export # systemctl start linstor-controller
You can only import a database from a previous backup if the currently installed version of LINSTOR is the same (or higher) version as the version that you created the backup from. If the currently installed LINSTOR version is higher than the version that the database backup was created from, when you import the backup the data will be restored with the same database scheme of the version used during the export. Then, the next time that the controller starts, the controller will detect that the database has an old scheme and it will automatically migrate the data to the scheme of the current version.
2.13.3. Converting Databases
Since the exported database file contains some metadata, an exported database file can be imported into a different database type than it was exported from.
This allows the user to convert, for example, from an etcd setup to an SQL based setup.
There is no special command for converting the database format. You only have to
specify the correct linstor.toml
configuration file by using the --config-directory
argument
(or updating the default /etc/linstor/linstor.toml
and specifying the database type that you want
to use before importing). See the LINSTOR User’s Guide for more
information about specifying a database type. Regardless of the type of database that the backup
was created from, it will be imported in the database type that is specified in the linstor.toml
configuration file.
3. Further LINSTOR Tasks
3.1. Creating a Highly Available LINSTOR Cluster
By default a LINSTOR cluster consists of exactly one active LINSTOR controller node. Making LINSTOR highly available involves providing replicated storage for the controller database, multiple LINSTOR controller nodes where only one is active at a time, and a service manager (here DRBD Reactor) that takes care of mounting and unmounting the highly available storage as well as starting and stopping the LINSTOR controller service on nodes.
3.1.1. Configuring Highly Available Storage
For configuring the highly available (HA) storage, you can use LINSTOR itself. One of the benefits of having the storage under LINSTOR control is that you can easily extend the HA storage to new cluster nodes.
First, create a new resource that is 200MiB in size and set the necessary DRBD options, as shown in the example commands below. You will need to adapt the storage pool name to match an existing storage pool in your environment.
# linstor resource-definition create linstor_db # linstor rd drbd-options --auto-promote=no linstor_db # linstor rd drbd-options --quorum=majority linstor_db # linstor rd drbd-options --on-suspended-primary-outdated=force-secondary linstor_db # linstor rd drbd-options --on-no-quorum=io-error linstor_db # linstor rd drbd-options --on-no-data-accessible=io-error linstor_db # linstor rd drbd-options --rr-conflict=retry-connect linstor_db # linstor volume-definition create linstor_db 200M # linstor resource create linstor_db --storage-pool pool1 --auto-place 3
It is crucial that your cluster qualifies for auto-quorum and uses the io-error
policy (see
Section Auto-Quorum Policies), and that auto-promote
is disabled.
From now on it is assumed that the resource’s name is linstor_db
. After creating the
linstor_db
resource, you can move the LINSTOR database to the new storage and create a
systemd mount service. First, stop the current controller service and disable it, as it will
be managed by DRBD Reactor later.
# systemctl disable --now linstor-controller
Next, create the systemd mount service.
# cat << EOF > /etc/systemd/system/var-lib-linstor.mount [Unit] Description=Filesystem for the LINSTOR controller [Mount] # you can use the minor like /dev/drbdX or the udev symlink What=/dev/drbd/by-res/linstor_db/0 Where=/var/lib/linstor EOF # mv /var/lib/linstor{,.orig} # mkdir /var/lib/linstor # chattr +i /var/lib/linstor # only if on LINSTOR >= 1.14.0 # drbdadm primary linstor_db # mkfs.ext4 /dev/drbd/by-res/linstor_db/0 # systemctl start var-lib-linstor.mount # cp -r /var/lib/linstor.orig/* /var/lib/linstor # systemctl start linstor-controller
Copy the /etc/systemd/system/var-lib-linstor.mount
mount file to all the cluster nodes that
you want to have the potential to run the LINSTOR controller service (standby controller nodes).
Again, do not systemctl enable
any of these services because DRBD Reactor will manage them.
3.1.2. Installing Multiple LINSTOR Controllers
The next step is to install LINSTOR controllers on all nodes that have access
to the linstor_db
DRBD resource (as they need to mount the DRBD volume) and
which you want to become a possible LINSTOR controller. It is important that the controllers
are manged by drbd-reactor
, so verify that the linstor-controller.service
is
disabled on all nodes! To be sure, execute systemctl disable linstor-controller
on all cluster nodes and systemctl stop linstor-controller
on all nodes except the one it is currently
running from the previous step. Also verify that you have set chattr +i /var/lib/linstor
on all potential controller
nodes if you use LINSTOR version equal or greater to 1.14.0.
3.1.3. Managing the Services
For starting and stopping the mount service and the linstor-controller service we use drbd-reactor
. Install this
component on all nodes that could become a LINSTOR controller and edit their /etc/drbd-reactor.d/linstor_db.toml
configuration
file. It should contain an enabled promoter plug-in section like this:
[[promoter]] id = "linstor_db" [promoter.resources.linstor_db] start = ["var-lib-linstor.mount", "linstor-controller.service"]
Depending on your requirements you might also want to set an on-stop-failure
action and set stop-services-on-exit
.
After that restart drbd-reactor
and enable it on all the nodes you configured it.
# systemctl restart drbd-reactor # systemctl enable drbd-reactor
Check that there are no warnings from drbd-reactor
service in the logs by running systemctl status drbd-reactor
.
As there is already an active LINSTOR controller things will just stay the way they are.
Run drbd-reactorctl status linstor_db
to check the health of the linstor_db target unit.
The last but nevertheless important step is to configure the LINSTOR
satellite services to not delete (and then regenerate) the resource file for the
LINSTOR controller DB at its startup. Do not edit the service files directly, but use systemctl edit
. Edit
the service file on all nodes that could become a LINSTOR controller and that are also LINSTOR satellites.
# systemctl edit linstor-satellite [Service] Environment=LS_KEEP_RES=linstor_db
After this change you should execute systemctl restart linstor-satellite
on all satellite nodes.
Be sure to configure your LINSTOR client for use with multiple controllers as described in the section titled, Using the LINSTOR Client and verify that you also configured your integration plug-ins (for example, the Proxmox plug-in) to be ready for multiple LINSTOR controllers. |
3.2. DRBD Clients
By using the --drbd-diskless
option instead of --storage-pool
you can
have a permanently diskless DRBD device on a node. This means that
the resource will appear as block device and can be mounted to the
filesystem without an existing storage-device. The data of the
resource is accessed over the network on another node with the
same resource.
# linstor resource create delta backups --drbd-diskless
The option --diskless was deprecated. Please use --drbd-diskless
or --nvme-initiator instead.
|
3.3. DRBD Consistency Groups (Multiple Volumes within a Resource)
The so called consistency group is a feature from DRBD. It is mentioned in this user’s guide, due to the fact that one of LINSTOR’s main functions is to manage storage-clusters with DRBD. Multiple volumes in one resource are a consistency group.
This means that changes on different volumes from one resource are getting replicated in the same chronological order on the other Satellites.
Therefore you don’t have to worry about the timing if you have interdependent data on different volumes in a resource.
To deploy more than one volume in a LINSTOR-resource you have to create two volume-definitions with the same name.
# linstor volume-definition create backups 500G # linstor volume-definition create backups 100G
3.4. Placing Volumes of One Resource in Different Storage Pools
This can be achieved by setting the StorPoolName
property to the volume
definitions before the resource is deployed to the nodes:
# linstor resource-definition create backups # linstor volume-definition create backups 500G # linstor volume-definition create backups 100G # linstor volume-definition set-property backups 0 StorPoolName pool_hdd # linstor volume-definition set-property backups 1 StorPoolName pool_ssd # linstor resource create alpha backups # linstor resource create bravo backups # linstor resource create charlie backups
Since the volume-definition create command is used without the --vlmnr option
LINSTOR assigned the volume numbers starting at 0. In the following two
lines the 0 and 1 refer to these automatically assigned volume numbers.
|
Here the ‘resource create’ commands do not need a --storage-pool
option.
In this case LINSTOR uses a ‘fallback’ storage pool. Finding that
storage pool, LINSTOR queries the properties of the following objects
in the following order:
-
Volume definition
-
Resource
-
Resource definition
-
Node
If none of those objects contain a StorPoolName
property, the controller
falls back to a hard-coded ‘DfltStorPool’ string as a storage pool.
This also means that if you forgot to define a storage pool prior deploying a resource, you will get an error message that LINSTOR could not find the storage pool named ‘DfltStorPool’.
3.5. Using LINSTOR Without DRBD
LINSTOR can be used without DRBD as well. Without DRBD, LINSTOR is able to provision volumes from LVM and ZFS backed storage pools, and create those volumes on individual nodes in your LINSTOR cluster.
Currently LINSTOR supports the creation of LVM and ZFS volumes with the option of layering some combinations of LUKS, DRBD, or NVMe-oF/NVMe-TCP on top of those volumes.
For example, assume we have a Thin LVM backed storage pool defined in
our LINSTOR cluster named, thin-lvm
:
# linstor --no-utf8 storage-pool list +--------------------------------------------------------------+ | StoragePool | Node | Driver | PoolName | ... | |--------------------------------------------------------------| | thin-lvm | linstor-a | LVM_THIN | drbdpool/thinpool | ... | | thin-lvm | linstor-b | LVM_THIN | drbdpool/thinpool | ... | | thin-lvm | linstor-c | LVM_THIN | drbdpool/thinpool | ... | | thin-lvm | linstor-d | LVM_THIN | drbdpool/thinpool | ... | +--------------------------------------------------------------+
We could use LINSTOR to create a Thin LVM on linstor-d
that’s 100GiB
in size using the following commands:
# linstor resource-definition create rsc-1 # linstor volume-definition create rsc-1 100GiB # linstor resource create --layer-list storage \ --storage-pool thin-lvm linstor-d rsc-1
You should then see you have a new Thin LVM on linstor-d
. You can
extract the device path from LINSTOR by listing your linstor resources
with the --machine-readable
flag set:
# linstor --machine-readable resource list | grep device_path "device_path": "/dev/drbdpool/rsc-1_00000",
If you wanted to layer DRBD on top of this volume, which is the default
--layer-list
option in LINSTOR for ZFS or LVM backed volumes, you
would use the following resource creation pattern instead:
# linstor resource-definition create rsc-1 # linstor volume-definition create rsc-1 100GiB # linstor resource create --layer-list drbd,storage \ --storage-pool thin-lvm linstor-d rsc-1
You would then see that you have a new Thin LVM backing a DRBD volume
on linstor-d
:
# linstor --machine-readable resource list | grep -e device_path -e backing_disk "device_path": "/dev/drbd1000", "backing_disk": "/dev/drbdpool/rsc-1_00000",
The following table shows which layer can be followed by which child-layer:
Layer | Child layer |
---|---|
DRBD |
CACHE, WRITECACHE, NVME, LUKS, STORAGE |
CACHE |
WRITECACHE, NVME, LUKS, STORAGE |
WRITECACHE |
CACHE, NVME, LUKS, STORAGE |
NVME |
CACHE, WRITECACHE, LUKS, STORAGE |
LUKS |
STORAGE |
STORAGE |
– |
One layer can only occur once in the layer-list |
For information about the prerequisites for the LUKS layer,
refer to the Encrypted Volumes section of this User’s Guide.
|
3.5.1. NVMe-oF/NVMe-TCP LINSTOR Layer
NVMe-oF/NVMe-TCP allows LINSTOR to connect diskless resources to a node with the same resource where the data is stored over NVMe fabrics. This leads to the advantage that resources can be mounted without using local storage by accessing the data over the network. LINSTOR is not using DRBD in this case, and therefore NVMe resources provisioned by LINSTOR are not replicated, the data is stored on one node.
NVMe-oF only works on RDMA-capable networks and NVMe-TCP on
networks that can carry IP traffic. You can use tools such as lshw or ethtool to verify
the capabilities of your network adapters.
|
To use NVMe-oF/NVMe-TCP with LINSTOR the package nvme-cli
needs to
be installed on every node which acts as a satellite and will use
NVMe-oF/NVMe-TCP for a resource. For example, on a DEB-based system, to install the package,
enter the following command:
# apt install nvme-cli
If you are not on a DEB-based system, use the suitable command for
installing packages on your operating system, for example, on SLES: zypper ; on RPM-based
systems: dnf .
|
To make a resource which uses NVMe-oF/NVMe-TCP an additional parameter has to be given as you create the resource-definition:
# linstor resource-definition create nvmedata -l nvme,storage
As default the -l (layer-stack) parameter is set to drbd,
storage when DRBD is used. If you want to create LINSTOR resources
with neither NVMe nor DRBD you have to set the -l parameter to only
storage .
|
To use NVMe-TCP rather than the default NVMe-oF, the following property needs to be set:
# linstor resource-definition set-property nvmedata NVMe/TRType tcp
The property NVMe/TRType
can alternatively be set on resource-group
or controller level.
Next, create the volume-definition for our resource:
# linstor volume-definition create nvmedata 500G
Before you create the resource on your nodes you have to know where the data will be stored locally and which node accesses it over the network.
First we create the resource on the node where our data will be stored:
# linstor resource create alpha nvmedata --storage-pool pool_ssd
On the nodes where the resource-data will be accessed over the network, the resource has to be defined as diskless:
# linstor resource create beta nvmedata --nvme-initiator
Now you can mount the resource nvmedata
on one of your nodes.
If your nodes have more than one NIC you should force the route between them for NVMe-of/NVME-TCP, otherwise multiple NICs could cause troubles. |
3.5.2. OpenFlex™ Layer
Since version 1.5.0 the additional Layer openflex
can be used in LINSTOR.
From LINSTOR’s perspective, the
OpenFlex
Composable Infrastructure takes the role of a combined layer acting as a
storage layer (like LVM) and also providing the allocated space as an NVMe target.
OpenFlex has a REST API which is also used by LINSTOR to operate with.
As OpenFlex combines concepts of LINSTOR’s storage as well as NVMe-layer, LINSTOR was
added both, a new storage driver for the storage pools as well as a dedicated openflex
layer which uses the mentioned REST API.
In order for LINSTOR to communicate with the OpenFlex-API, LINSTOR needs some additional
properties, which can be set once on controller
level to take LINSTOR-cluster wide effect:
-
StorDriver/Openflex/ApiHost
specifies the host or IP of the API entry-point -
StorDriver/Openflex/ApiPort
this property is glued with a colon to the previous to form the basichttp://ip:port
part used by the REST callsStorDriver/Openflex/UserName
the REST username -
StorDriver/Openflex/UserPassword
the password for the REST user
Once that is configured, we can now create LINSTOR objects to represent the OpenFlex architecture. The theoretical mapping of LINSTOR objects to OpenFlex objects are as follows: Obviously an OpenFlex storage pool is represented by a LINSTOR storage pool. As the next thing above a LINSTOR storage pool is already the node, a LINSTOR node represents an OpenFlex storage device. The OpenFlex objects above storage device are not mapped by LINSTOR.
When using NVMe, LINSTOR was designed to run on both sides, the NVMe target as well as on the NVMe initiator side. In the case of OpenFlex, LINSTOR cannot (or even should not) run on the NVMe target side as that is completely managed by OpenFlex. As LINSTOR still needs nodes and storage pools to represent the OpenFlex counterparts, the LINSTOR client was extended with special node create commands since 1.0.14. These commands not only accept additionally needed configuration data, but also starts a “special satellite” besides the already running controller instance. These special satellites are completely LINSTOR managed. They will shut down when the controller shuts down and will be started again when the controller starts.
The new client command for creating a “special satellite” representing an OpenFlex storage device is:
$ linstor node create-openflex-target ofNode1 192.168.166.7 000af795789d
The arguments are as follows:
-
ofNode1
is the node name which is also used by the standardlinstor node create
command -
192.168.166.7
is the address on which the provided NVMe devices can be accessed. As the NVMe devices are accessed by a dedicated network interface, this address differs from the address specified with the propertyStorDriver/Openflex/ApiHost
. The latter is used for the management / REST API. -
000af795789d
is the identifier for the OpenFlex storage device.
The last step of the configuration is the creation of LINSTOR storage pools:
$ linstor storage-pool create openflex ofNode1 sp0 0
-
ofNode1
andsp0
are the node name and storage pool name, respectively, just as usual for the LINSTOR’screate storage pool
command -
The last
0
is the identifier of the OpenFlex storage pool within the previously defined storage device
Once all necessary storage pools are created in LINSTOR, the next steps are similar to the usage of using an NVMe resource with LINSTOR. Here is a complete example:
# set the properties once linstor controller set-property StorDriver/Openflex/ApiHost 10.43.7.185 linstor controller set-property StorDriver/Openflex/ApiPort 80 linstor controller set-property StorDriver/Openflex/UserName myusername linstor controller set-property StorDriver/Openflex/UserPassword mypassword # create a node for openflex storage device "000af795789d" linstor node create-openflex-target ofNode1 192.168.166.7 000af795789d # create a usual linstor satellite. later used as nvme initiator linstor node create bravo # create a storage pool for openflex storage pool "0" within storage device "000af795789d" linstor storage-pool create openflex ofNode1 sp0 0 # create resource- and volume-definition linstor resource-definition create backupRsc linstor volume-definition create backupRsc 10G # create openflex-based nvme target linstor resource create ofNode1 backupRsc --storage-pool sp0 --layer-list openflex # create openflex-based nvme initiator linstor resource create bravo backupRsc --nvme-initiator --layer-list openflex
In case a node should access the OpenFlex REST API through a different host than specified withlinstor controller set-property StorDriver/Openflex/ApiHost 10.43.7.185 you can always use LINSTOR’s
inheritance mechanism for properties. That means simply define the same property on the node-level
you need it, i.e.linstor node set-property ofNode1 StorDriver/Openflex/ApiHost 10.43.8.185
|
3.5.3. Writecache Layer
A DM-Writecache device is composed of two devices: one storage device and one cache device. LINSTOR can setup such a writecache device, but needs some additional information, like the storage pool and the size of the cache device.
# linstor storage-pool create lvm node1 lvmpool drbdpool # linstor storage-pool create lvm node1 pmempool pmempool # linstor resource-definition create r1 # linstor volume-definition create r1 100G # linstor volume-definition set-property r1 0 Writecache/PoolName pmempool # linstor volume-definition set-property r1 0 Writecache/Size 1% # linstor resource create node1 r1 --storage-pool lvmpool --layer-list WRITECACHE,STORAGE
The two properties set in the examples are mandatory, but can also be set on
controller level which would act as a default for all resources with WRITECACHE
in their
--layer-list
. However, please note that the Writecache/PoolName
refers to
the corresponding node. If the node does not have a storage pool named pmempool
you will
get an error message.
The 4 mandatory parameters required by
DM-Writecache
are either configured through a property or figured out by LINSTOR.
The optional properties listed in the mentioned link can also be set through a property.
Please see linstor controller set-property --help
for a list of Writecache/*
property-keys.
Using --layer-list DRBD,WRITECACHE,STORAGE
while having DRBD configured to use
external metadata, only the backing device will use a writecache, not the
device holding the external metadata.
3.5.4. Cache Layer
LINSTOR can also setup a DM-Cache
device, which is very similar to the DM-Writecache from the previous section. The major difference
is that a cache device is composed by three devices: one storage device, one cache device and one
meta device. The LINSTOR properties are quite similar to those of the writecache but are located
in the Cache
namespace:
# linstor storage-pool create lvm node1 lvmpool drbdpool # linstor storage-pool create lvm node1 pmempool pmempool # linstor resource-definition create r1 # linstor volume-definition create r1 100G # linstor volume-definition set-property r1 0 Cache/CachePool pmempool # linstor volume-definition set-property r1 0 Cache/Cachesize 1% # linstor resource create node1 r1 --storage-pool lvmpool --layer-list CACHE,STORAGE
Rather than Writecache/PoolName (as when configuring the Writecache layer) the
Cache layer’s only required property is called Cache/CachePool . The reason for this
is that the Cache layer also has a Cache/MetaPool which can be configured separately
or it defaults to the value of Cache/CachePool .
|
Please see linstor controller set-property --help
for a list of Cache/*
property-keys and default values for omitted properties.
Using --layer-list DRBD,CACHE,STORAGE
while having DRBD configured to use external
metadata, only the backing device will use a cache, not the device holding the external
metadata.
3.5.5. Storage Layer
The storage layer will provide new devices from well known volume managers like LVM, ZFS or
others. Every layer combination needs to be based on a storage layer, even if the resource
should be diskless – for that type there is a dedicated diskless
provider type.
For a list of providers with their properties please see Storage Providers.
For some storage providers LINSTOR has special properties:
-
StorDriver/WaitTimeoutAfterCreate
: If LINSTOR expects a device to appear after creation (for example after calls oflvcreate
,zfs create
,…), LINSTOR waits per default 500ms for the device to appear. These 500ms can be overridden by this property. -
StorDriver/dm_stats
: If set totrue
LINSTOR callsdmstats create $device
after creation anddmstats delete $device --allregions
after deletion of a volume. Currently only enabled for LVM and LVM_THIN storage providers.
3.6. Storage Providers
LINSTOR has a few storage providers. The most used ones are LVM and ZFS. But also for those two providers there are already sub-types for their thin-provisioned variants.
-
Diskless: This provider type is mostly required to have a storage pool that can be configured with LINSTOR properties like
PrefNic
as described in Managing Network Interface Cards. -
LVM / LVM-Thin: The adminstrator is expected to specify the LVM volume group or the thin-pool (in form of “LV/thinpool”) to use the corresponding storage type. These drivers support following properties for fine-tuning:
-
StorDriver/LvcreateOptions
: The value of this property is appended to everylvcreate …
call LINSTOR executes.
-
-
ZFS / ZFS-Thin: The administrator is expected to specify the ZPool that LINSTOR should use. These drivers support following properties for fine-tuning:
-
StorDriver/ZfscreateOptions
: The value of this property is appended to everyzfs create …
call LINSTOR executes.
-
-
File / FileThin: Mostly used for demonstration / experiments. LINSTOR will basically reserve a file in a given directory and will configure a loop device on top of that file.
-
OpenFlex: This special storage provider currently requires to be run on a “special satellite”. Please see OpenFlex™ Layer for more details.
-
EXOS: This special storage provider is currently required to be run on a “special satellite”. Please see the EXOS Integration chapter.
-
SPDK: The administrator is expected to specify the logical volume store which LINSTOR should use. The usage of this storage provider implies the usage of the NVME Layer.
-
Remote-SPDK: This special storage provider currently requires to be run on a “special satellite”. Please see Remote SPDK Provider for more details.
-
3.6.1. Remote SPDK Provider
A storage pool with the type remote SPDK can only be created on a “special satellite”. For this you first need to start a new satellite using the command:
$ linstor node create-remote-spdk-target nodeName 192.168.1.110
This will start a new satellite instance running on the same machine as the controller. This special satellite will do all the REST based RPC communication towards the remote SPDK proxy. As the help message of the LINSTOR command shows, the administrator might want to use additional settings when creating this special satellite:
$ linstor node create-remote-spdk-target -h usage: linstor node create-remote-spdk-target [-h] [--api-port API_PORT] [--api-user API_USER] [--api-user-env API_USER_ENV] [--api-pw [API_PW]] [--api-pw-env API_PW_ENV] node_name api_host
The difference between the --api-*
and their corresponding --api-\*-env
versions is that the
version with the -env
ending will look for an environment variable containing the actual value to use
whereas the --api-\*
version directly take the value which is stored in the LINSTOR property.
Administrators might not want to save the --api-pw
in plain text, which would be clearly visible
using commands like linstor node list-property <nodeName>
.
Once that special satellite is up and running the actual storage pool can be created:
$ linstor storage-pool create remotespdk -h usage: linstor storage-pool create remotespdk [-h] [--shared-space SHARED_SPACE] [--external-locking] node_name name driver_pool_name
Whereas node_name
is self-explanatory, name
is the name of the LINSTOR storage pool and
driver_pool_name
refers to the SPDK logical volume store.
Once this remotespdk storage pool is created the remaining procedure is quite similar as
using NVMe: First the target has to be created by creating a simple “diskful” resource followed
by a second resource having the --nvme-initiator
option enabled.
3.7. Managing Network Interface Cards
LINSTOR can deal with multiple network interface cards (NICs) in a machine. They are called “net interfaces” in LINSTOR speak.
When a satellite node is created a first net interface gets created implicitly
with the name default . You can use the --interface-name option of the node create
command to give it a different name, when you create the satellite node.
|
For existing nodes, additional net interfaces are created like this:
# linstor node interface create node-0 10G_nic 192.168.43.231
Net interfaces are identified by the IP address only, the name is arbitrary and is not related to the NIC name used by Linux. You can then assign the net interface to a node so that the node’s DRBD traffic will be routed through the corresponding NIC.
# linstor node set-property node-0 PrefNic 10G_nic
It is also possible to set the PrefNic property on a storage pool. DRBD traffic from
resources using the storage pool will be routed through the corresponding NIC. However, you need
to be careful here. Any DRBD resource that requires Diskless storage, for example, diskless
storage acting in a tiebreaker role for DRBD quorum purposes, will go through the default
satellite node net interface, until you also set the PrefNic property for the default net
interface. Setups can become complex. It is far easier and safer, if you can get away with it,
to set the PrefNic property at the node level. This way, all storage pools on the node,
including Diskless storage pools, will use your preferred NIC.
|
If you need to add an interface for only controller-satellite traffic, you can add an
interface using the above node interface create
command. Then you modify the connection to
make it the active controller-satellite connection. For example, if you added an interface named
1G-satconn
on all nodes, after adding the interface, you can then tell LINSTOR to use this
interface for controller-satellite traffic by entering the following command:
# linstor node interface modify node-0 1G-satconn --active
You can verify this change by using the linstor node interface list node-0
command. Output
from the command should show that the StltCon
label applies to the 1G-satconn
interface.
While this method routes DRBD traffic through a specified NIC, it is not possible through
linstor
commands only, to route LINSTOR controller-client traffic through a specific NIC, for
example, commands that you issue from a LINSTOR client to the controller. To achieve this, you
can either:
-
Specify a LINSTOR controller by using methods outlined in Using the LINSTOR Client and have the only route to the controller as specified be through the NIC that you want to use for controller-client traffic.
-
Use Linux tools such as
ip route
andiptables
to filter LINSTOR client-controller traffic, port number 3370, and route it through a specific NIC.
3.7.1. Creating Multiple DRBD Paths with LINSTOR
To use
multiple
network paths for DRBD setups, the PrefNic
property is not sufficient. Instead the linstor
node interface
and linstor resource-connection path
commands should be used, as shown below.
# linstor node interface create alpha nic1 192.168.43.221 # linstor node interface create alpha nic2 192.168.44.221 # linstor node interface create bravo nic1 192.168.43.222 # linstor node interface create bravo nic2 192.168.44.222 # linstor resource-connection path create alpha bravo myResource path1 nic1 nic1 # linstor resource-connection path create alpha bravo myResource path2 nic2 nic2
The first four commands in the example define a network interface (nic1
and nic2
) for each
node (alpha
and bravo
) by specifying the network interface’s IP address. The last two
commands create network path entries in the DRBD .res
file that LINSTOR generates. This is the
relevant part of the resulting .res
file:
resource myResource { ... connection { path { host alpha address 192.168.43.221:7000; host bravo address 192.168.43.222:7000; } path { host alpha address 192.168.44.221:7000; host bravo address 192.168.44.222:7000; } } }
While it is possible to specify a port number to be used for LINSTOR satellite traffic when creating a node interface, this port number is ignored when creating a DRBD resource connection path. Instead, the command will assign a port number dynamically, starting from port number 7000 and incrementing up. |
How Adding a New DRBD Path Affects the Default Path
The NIC that is first in order on a LINSTOR satellite node is named the default
net interface.
DRBD traffic traveling between two nodes that do not have an explicitly configured resource
connection path will take an implicit path that uses the two nodes’ default
net interfaces.
When you add a resource connection path between two nodes for a DRBD-backed resource, DRBD
traffic between the two nodes will use this new path only, although a default
network
interface will still exist on each node. This may be significant if your new path uses different
NICs than the implicit default path.
To use the default path again, in addition to any new paths, you will need to explicitly add it. For example:
# linstor resource-connection path create alpha bravo myResource path3 default default
Although the newly created path3
uses net interfaces that are named default
on the two
nodes, the path itself is not a default path because other paths exist, namely path1
and
path2
. The new path, path3
, will just act as a third possible path, and DRBD traffic and
path selection behavior will be as described in the next section.
Multiple DRBD Paths Behavior
The behavior of a multiple DRBD paths configuration will be different depending on the DRBD transport type. From the DRBD User’s Guide[4]:
“The TCP transport uses one path at a time. If the backing TCP connections get dropped, or show timeouts, the TCP transport implementation tries to establish a connection over the next path. It goes over all paths in a round-robin fashion until a connection gets established.
“The RDMA transport uses all paths of a connection concurrently and it balances the network traffic between the paths evenly.”
3.8. Encrypted Volumes
LINSTOR can handle transparent encryption of DRBD volumes. dm-crypt is used to encrypt the provided storage from the storage device.
To use dm-crypt please verify that cryptsetup is installed before
you start the satellite.
|
Basic steps to use encryption:
-
Create a master passphrase
-
Add
luks
to the layer-list. Note that all plug-ins (e.g., Proxmox) require a DRBD layer as the top most layer if they do not explicitly state otherwise. -
Don’t forget to re-enter the master passphrase after a controller restart.
3.8.1. Encryption Commands
Below are details about the commands.
Before LINSTOR can encrypt any volume a master passphrase needs to be created. This can be done with the linstor-client.
# linstor encryption create-passphrase
crypt-create-passphrase
will wait for the user to input the initial master passphrase
(as all other crypt commands will with no arguments).
If you ever want to change the master passphrase this can be done with:
# linstor encryption modify-passphrase
The luks
layer can be added when creating the resource-definition or the resource
itself, whereas the former method is recommended since it will be automatically applied
to all resource created from that resource-definition.
# linstor resource-definition create crypt_rsc --layer-list luks,storage
To enter the master passphrase (after controller restart) use the following command:
# linstor encryption enter-passphrase
Whenever the linstor-controller is restarted, the user has to send the master passphrase to the controller, otherwise LINSTOR is unable to reopen or create encrypted volumes. |
3.8.2. Automatic Passphrase
It is possible to automate the process of creating and re-entering the master passphrase.
To use this, either an environment variable called MASTER_PASSPHRASE
or an entry in
/etc/linstor/linstor.toml
containing the master passphrase has to be created.
The required linstor.toml
looks like this:
[encrypt] passphrase="example"
If either one of these is set, then every time the controller starts it will check whether a master passphrase already exists. If there is none, it will create a new master passphrase as specified. Otherwise, the controller enters the passphrase.
If a master passphrase is already configured, and it is not the same one as specified
in the environment variable or linstor.toml , the controller will be unable to re-enter the
master passphrase and react as if the user had entered a wrong passphrase.
This can only be resolved through manual input from the user, using the same commands as if
the controller was started without the automatic passphrase.
|
In case the master passphrase is set in both an environment variable and the linstor.toml ,
only the master passphrase from the linstor.toml will be used.
|
3.9. Checking Cluster State
LINSTOR provides various commands to check the state of your cluster. These commands start with a ‘list’ precursor, after which, various filtering and sorting options can be used. The ‘–groupby’ option can be used to group and sort the output in multiple dimensions.
# linstor node list # linstor storage-pool list --groupby Size
3.10. Evacuating a Node
You can use the LINSTOR command node evacuate
to evacuate a node of its resources, for
example, if you are preparing to delete a node from your cluster, and you need the node’s
resources moved to other nodes in the cluster. After successfully evacuating a node, the node’s
LINSTOR status will show as “EVACUATE” rather than “Online”, and it will have no LINSTOR
resources on it.
If you are evacuating a node where LINSTOR is deployed within another environment, such as Kubernetes, or OpenNebula, you need to move the node’s LINSTOR-backed workload to another node in your cluster before evacuating its resources. For special actions and considerations within a Kubernetes environment, see the Evacuating a Node in Kubernetes section. For a LINSTOR node in OpenNebula, you need to perform a live migration of the OpenNebula LINSTOR-backed virtual machines that your node hosts, to another node in your cluster, before evacuating the node’s resources. |
Evacuate a node using the following steps:
-
Determine if any resources on the node that you want to evacuate are “InUse”. The “InUse” status corresponds to a resource being in a DRBD Primary state. Before you can evacuate a node successfully, none of the resources on the node should be “InUse”, otherwise LINSTOR will fail to remove the “InUse” resources from the node as part of the evacuation process.
-
Run
linstor node evacuate <node_name>
. You will get a warning if there is no suitable replacement node for a resource on the evacuating node. For example, if you have three nodes and you want to evacuate one, but your resource group sets a placement count of three, you will get a warning that will prevent the node from removing the resources from the evacuating node. -
Verify that the status of
linstor node list
for your node is “EVACUATE” rather than “Online”. -
Check the “State” status of resources on your node, by using the
linstor resource list
command. You should see syncing activity that will last for sometime, depending on the size of the data sets in your node’s resources. -
List the remaining resources on the node by using the command
linstor resource list --nodes <node_name>
. If any are left, verify whether they are just waiting for the sync to complete. -
Verify that there are no resources on the node, by using the
linstor resource list
command. -
Remove the node from the cluster by using the command
linstor node delete <node_name>
.
3.10.1. Evacuating Multiple Nodes
Some evacuation cases may need special planning. For example, if you are evacuating more than one node, you can exclude the nodes from participating in LINSTOR’s resource autoplacer. You can do this by using the following command on each node that you want to evacuate:
# linstor node set-property <node_name> AutoplaceTarget false
This ensures that LINSTOR will not place resources from a node that you are evacuating onto another node that you plan on evacuating.
3.10.2. Restoring an Evacuating Node
If you already ran a node evacuate
command that has either completed or still has resources in
an “Evacuating” state, you can remove the “Evacuating” state from a node by using the node
restore
command. This will work so long as you have not yet run a node delete
command.
After restoring the node, you should use the node set-property <node_name> AutoplaceTarget
true
command, if you previously set the AutoplaceTarget
property to “false”. This way,
LINSTOR can again place resources onto the node automatically, to fulfill placement count
properties that you might have set for resources in your cluster.
If LINSTOR has already evacuated resources when running a node restore command,
evacuated resources will not automatically return to the node. If LINSTOR is still in the
process of evacuating resources, this process will continue until LINSTOR has placed the
resources on other nodes. You will need to manually “move” the resources that were formerly on
the restored node. You can do this by first creating the resources on the restored node and then
deleting the resources from another node where LINSTOR may have placed them. You can use the
resource list command to show you on which nodes your resources are placed.
|
3.11. Managing Snapshots
Snapshots are supported with thin LVM and ZFS storage pools.
3.11.1. Creating a Snapshot
Assuming a resource definition named ‘resource1’ which has been placed on some nodes, a snapshot can be created as follows:
# linstor snapshot create resource1 snap1
This will create snapshots on all nodes where the resource is present. LINSTOR will ensure that consistent snapshots are taken even when the resource is in active use.
Setting the resource-definition property AutoSnapshot/RunEvery
LINSTOR will automatically create snapshots every X minute.
The optional property AutoSnapshot/Keep
can be used to clean-up old snapshots
which were created automatically. No manually created snapshot will be cleaned-up / deleted.
If AutoSnapshot/Keep
is omitted (or ⇐ 0), LINSTOR will keep the last 10 snapshots
by default.
# linstor resource-definition set-property AutoSnapshot/RunEvery 15 # linstor resource-definition set-property AutoSnapshot/Keep 5
3.11.2. Restoring a Snapshot
The following steps restore a snapshot to a new resource. This is possible even when the original resource has been removed from the nodes where the snapshots were taken.
First define the new resource with volumes matching those from the snapshot:
# linstor resource-definition create resource2 # linstor snapshot volume-definition restore --from-resource resource1 \ --from-snapshot snap1 --to-resource resource2
At this point, additional configuration can be applied if necessary. Then, when ready, create resources based on the snapshots:
# linstor snapshot resource restore --from-resource resource1 \ --from-snapshot snap1 --to-resource resource2
This will place the new resource on all nodes where the snapshot is present.
The nodes on which to place the resource can also be selected explicitly;
see the help (linstor snapshot resource restore -h
).
3.11.3. Rolling Back to a Snapshot
LINSTOR can roll a resource back to a snapshot state. The resource must not be in use. That is, it may not be mounted on any nodes. If the resource is in use, consider whether you can achieve your goal by restoring the snapshot instead.
Rollback is performed as follows:
# linstor snapshot rollback resource1 snap1
A resource can only be rolled back to the most recent snapshot. To roll back to an older snapshot, first delete the intermediate snapshots.
3.11.4. Removing a Snapshot
An existing snapshot can be removed as follows:
# linstor snapshot delete resource1 snap1
3.11.5. Shipping a Snapshot
Snapshots can be shipped between LINSTOR nodes or between different LINSTOR clusters, as well as to an S3 storage such as Amazon S3 or min.io.
The following tools need to be installed on the satellites that are going to send or receive snapshots:
-
zstd
is needed to compress the data before it is being shipped -
thin-send-recv
is needed to ship data when using lvm-thin
The satellite needs to be restarted after installing these tools, otherwise LINSTOR will not be able to use them. |
Remotes
In a LINSTOR cluster, the definition of a shipping target is called a remote. Currently, there are two different types of remotes: LINSTOR remotes and S3 remotes. LINSTOR remotes are used to ship snapshots to a different LINSTOR cluster, while S3 remotes are needed to ship snapshots to AWS S3, min.io or any other service using S3 compatible object storage.
Since a remote needs to store sensitive data, such as passwords, it is neccessary to have encryption enabled whenever you want to use a remote in any way. How to set up LINSTOR’s encryption is described here. |
To create an S3 remote, LINSTOR will need to know the endpoint (that is, the URL of the target S3 server), the name of the target bucket, the region the S3 server is in, as well as the access-key and secret-key used to access the bucket. If the command is sent without adding the secret-key, a prompt will pop up to enter it in. The command should look like this:
# linstor remote create s3 myRemote s3.us-west-2.amazonaws.com \ my-bucket us-west-2 admin password
Usually, LINSTOR uses the endpoint and bucket to create an URL using the virtual-hosted-style
for its access to the given bucket (for example my-bucket.s3.us-west-2.amazonaws.com). Should your setup not
allow access this way, change the remote to path-style access (for example s3.us-west-2.amazonaws.com/my-bucket)
by adding the --use-path-style argument to make LINSTOR combine the parameters accordingly.
|
To create a LINSTOR remote, only the URL or IP address of the controller of the target cluster is needed. The command goes as follows:
# linstor remote create linstor myRemote 192.168.0.15
Additionally, to ship LUKS-based (encrypted) backups, it is necessary to add the --passphrase
and --cluster-id
arguments to the command. This is used to save the passphrase and cluster ID of
the target cluster to the remote respectively. For more details on shipping LUKS-based backups
between two LINSTOR clusters, see this chapter.
To see all the remotes known to the local cluster, use linstor remote list
. To delete a remote, use
linstor remote delete myRemoteName
. Should an existing remote need altering, use linstor remote
modify
to change it.
Shipping Snapshots to S3
All that is needed to ship a snapshot to S3 is to create an S3-remote that the current cluster can reach as well as the resource that should be shipped. Then, simply use the following command to ship it there:
# linstor backup create myRemote myRsc
This command will create a snapshot of your resource and ship it to the given remote. If this
isn’t the first time you shipped a backup of this resource (to that remote) and the snapshot
of the previous backup hasn’t been deleted yet, an incremental backup will be shipped.
To force the creation of a full backup, add the --full
argument to the command. Getting a
specific node to ship the backup is also possible by using --node myNode
, but if the specified
node is not available or only has the resource diskless, a different node will be chosen.
To see which backups exist in a specific remote, use linstor backup list myRemote
. A resource-name
can be added to the command as a filter to only show backups of that specific resource by using the
argument --resource myRsc
. If you use the --other
argument, only entries in the bucket that LINSTOR
does not recognize as a backup will be shown. LINSTOR always names backups in a certain way, and
as long as an item in the remote is named according to this schema, it is assumed that it is a backup
created by LINSTOR – so this list will show everything else.
There are several options when it comes to deleting backups:
-
linstor backup delete all myRemote
: This command deletes ALL S3-objects on the given remote, provided that they are recognized to be backups, that is, fit the expected naming schema. There is the option--cluster
to only delete backups that were created by the current cluster. -
linstor backup delete id myRemote my-rsc_back_20210824_072543
: This command deletes a single backup from the given remote – namely the one with the given id, which consists of the resource-name, the automatically generated snapshot-name (back_timestamp) and, if set, the backup-suffix. The option--prefix
lets you delete all backups starting with the given id. The option--cascade
deletes not only the specified backup, but all other incremental backups depending on it. -
linstor backup delete filter myRemote …
: This command has a few different arguments to specify a selection of backups to delete.-t 20210914_120000
will delete all backups made before 12 o’clock on the 14th of September, 2021.-n myNode
will delete all backups uploaded by the given node.-r myRsc
will delete all backups with the given resource name. These filters can be combined as needed. Finally,--cascade
deletes not only the selected backup(s), but all other incremental backups depending on any of the selected backups. -
linstor backup delete s3key myRemote randomPictureInWrongBucket
: This command will find the object with the given S3-key and delete it – without considering anything else. This should only be used to either delete non-backup items from the remote, or to clean up a broken backup that is no longer deleteable by other means. Using this command to delete a regular, working backup will break that backup, so beware!
All commands that have the --cascade option will NOT delete a backup that has
incremental backups depending on it unless you explicitly add that option.
|
All linstor backup delete … commands have the --dry-run option, which will
give you a list of all the S3-objects that will be deleted. This can be used to ensure
nothing that should not be deleted is accidentally deleted.
|
Maybe the most important task after creating a backup is restoring it. To do so, only the remote is needed – but it is also possible to restore into an existing resource definition with no existing snapshots nor resources. There are two options for the command:
# linstor backup restore myRemote myNode targetRsc --resource sourceRsc # linstor backup restore myRemote myNode targetRsc --id sourceRsc_back_20210824_072543
Either --resource (-r)
or --id
must be used, but you cannot use both of them together. -r
is used to
restore the latest backup of the resource specified with this option, while --id
restores the
exact backup specified by the given id, and can therefore be used to restore backups other than
the most recent.
If the backup to be restored includes a LUKS layer, the --passphrase
argument is required. With
it, the passphrase of the original cluster of the backup needs to be set so that LINSTOR can decrypt
the volumes after download and re-encrypt them with the local passphrase.
The backup restore will download all the snapshots from the last full backup up to the specified
backup. Afterwards, it restores the snapshots into a new resource. If that last step should be skipped,
the --download-only
option needs to be added to the command.
Backups can be downloaded from any cluster, not just the one that uploaded them, provided that the setup
is correct. Specifically, the target resource cannot have any existing resources or snapshots, and the
storage pool(s) used need to have the same storage providers. If the storage pool(s) on the target
node have the exact same names as on the cluster the backup was created on, no extra action is
necessary. Should they have different names, the option --storpool-rename
needs to be used. It
expects at least one oldname=newname
pair. For every storage pool of the original backup that
is not named in that list, it will be assumed that its name is exactly the same on the target node.
To find out exactly which storage pools need to be renamed, as well as how big the download and the
restored resource will be, the command linstor backup info myRemote …
can be used. Similar to the restore
command, either -r
or --id
need to be given, which add the same restrictions as with that command.
To see how much space will be left over in the local storage pools after a restore, the argument -n myNode
needs to be added. Just like with a restore, it assumes the storage pool names are exactly the same
on the given node as with the backup. Should that not be the case, again, just like with the restore
command, --storpool-rename
should be used.
Shipping Snapshots Between Two LINSTOR Clusters
Shipping a snapshot directly between two LINSTOR clusters can be done with a LINSTOR remote as well as a resource definition with at least one diskful resource on the source side (where the shipping command is issued). On the target side, you need to create a LINSTOR remote with the cluster ID of the source (remote) cluster:
$ linstor remote create linstor --cluster-id <SOURCE_CLUSTER_ID> <NAME> <URL>
If you do not specify the cluster ID of your source cluster when you create a LINSTOR
remote on your target cluster, you will receive an “Unknown Cluster” error when you try to ship
a backup. To get the cluster ID of your source cluster, you can enter the command linstor
controller list-properties|grep -i cluster from the source cluster.
|
In the remote create
command shown above, <NAME>
is an arbitrary name that you specify to
identify the remote. <URL>
is either the IP address of the source (remote) LINSTOR controller
or its resolvable hostname. If you have configured a highly available LINSTOR controller, use
its virtual IP address (VIP) or the VIP’s resolvable name.
Snapshot Shipping Within a Single LINSTOR Cluster
If you want to ship a snapshot inside the same cluster, you just need to create a LINSTOR remote that points to the local controller.
Specifying a LINSTOR Passphrase When Creating a Remote
When the snapshot that you want to ship contains a LUKS layer, the remote on the target cluster also needs the passphrase of the source cluster set when you create the remote. This is because the LINSTOR passphrase is used to encrypt the LUKS passphrase. To specify the source cluster’s LINSTOR passphrase when you create a LINSTOR remote on the target cluster, enter:
$ linstor --controllers <TARGET_CONTROLLER> remote create linstor \ --cluster-id <SOURCE_CLUSTER_ID> --passphrase <SOURCE_CONTROLLER_PASSPHRASE> <NAME> <URL>
For LINSTOR to LINSTOR snapshot shipping, you must also create a LINSTOR remote on the source cluster. For simplicity sake, although not strictly necessary, you can specify the target cluster’s LINSTOR passphrase when you create a LINSTOR remote for the target cluster on the source cluster, before you ship backups or snapshots. On the source cluster, enter:
$ linstor --controllers <SOURCE_CONTROLLER> remote create linstor \ --cluster-id <TARGET_CLUSTER_ID> --passphrase <TARGET_CONTROLLER_PASSPHRASE> <NAME> <URL>
If you are specifying a LINSTOR controller node (perhaps because you have a highly available controller), when creating a remote, you can specify the controller either by an IP address or a resolvable hostname. |
Shipping a Backup of a LINSTOR Resource
The command to ship a backup is:
# linstor backup ship myRemote localRsc targetRsc
Additionally, you can use --source-node
and --target-node
to specify which node should send and
receive the backup respectively. In case those nodes are not available, a different one will be chosen
automatically.
If targetRsc
is already a deployed resource on the remote cluster, snapshots in the
backup shipping for localRsc
will ship to the remote cluster but they will not be restored to
the remote cluster. The same is true if you specify the --download-only
option with the
linstor backup ship
command.
Controlling How Many Shipments Are Active at the Same Time
There might be cases where an automated task (be it LINSTOR’s scheduled shipping or an external tool) starts too many shipments at once, leading to an overload of the network or some of the nodes sending the backups.
In a case like this the solution is to reduce the amount of shipments that can happen at the same
time on the same node. This is done by using the property BackupShipping/MaxConcurrentBackupsPerNode
.
This property can be set either on the controller or on a specific node.
The expected value for this property is a number. Setting it to any negative number will be interpreted as “no limit”, while setting it to zero will result in this specific node not being eligible to ship any backups – or completely disabling backup shipping if the property is set to 0 on the controller.
Any other positive number is treated as a limit of concurrently active shippings per node. To determine which node will send a backup shipment, LINSTOR uses the following logic in the order shown:
-
The node specified in the command (
--source-node
for shippings to another cluster,--node
for shipping to S3 compatible storage) will ship the backup. -
The node that has the most available backup slots will ship the backup.
-
If no node has an available backup slot, the shipment will be added to a queue and started as soon as a different shipment has finished which leads to a backup slot becoming available.
Shipping a Snapshot in the Same Cluster
Both, the source as well as the target node have to have the resource for snapshot shipping deployed. Additionally, the target resource has to be deactivated.
# linstor resource deactivate nodeTarget resource1
Deactivating a resource with DRBD in its layer-list can NOT be reactivated again. However, a successfully shipped snapshot of a DRBD resource can still be restored into a new resource. |
To manually start the snapshot-shipping, use:
# linstor snapshot ship --from-node nodeSource --to-node nodeTarget --resource resource1
The snapshot ship command is considered deprecated and any bugs found
with it will not be fixed. Instead, use the backup ship command with a remote pointing
to your local controller. For more details, see the previous section.
|
By default, the snapshot-shipping uses TCP ports from the range 12000-12999. To change
this range, the property SnapshotShipping/TcpPortRange
, which accepts a to-from range,
can be set on the controller:
# linstor controller set-property SnapshotShipping/TcpPortRange 10000-12000
A resource can also be periodically shipped. To accomplish this, it is mandatory to
set the properties SnapshotShipping/TargetNode
as well as SnapshotShipping/RunEvery
on the resource-definition.
SnapshotShipping/SourceNode
can also be set, but if omitted LINSTOR will choose
an active resource of the same resource-definition.
To allow incremental snapshot-shipping, LINSTOR has to keep at least the last shipped
snapshot on the target node. The property SnapshotShipping/Keep
can be used to specify
how many snapshots LINSTOR should keep. If the property is not set (or ⇐ 0) LINSTOR
will keep the last 10 shipped snapshots by default.
# linstor resource-definition set-property resource1 SnapshotShipping/TargetNode nodeTarget # linstor resource-definition set-property resource1 SnapshotShipping/SourceNode nodeSource # linstor resource-definition set-property resource1 SnapshotShipping/RunEvery 15 # linstor resource-definition set-property resource1 SnapshotShipping/Keep 5
3.12. Scheduled Backup Shipping
Starting with LINSTOR Controller version 1.19.0 and working with LINSTOR client version 1.14.0 or above, you can configure scheduled backup shipping for deployed LINSTOR resources.
Scheduled backup shipping consists of three parts:
-
A data set that consists of one or more deployed LINSTOR resources that you want to backup and ship
-
A remote destination to ship backups to (another LINSTOR cluster or an S3 instance)
-
A schedule that defines when the backups should ship
LINSTOR backup shipping only works for deployed LINSTOR resources that are backed by LVM and ZFS storage pools, because these are the storage pool types with snapshot support in LINSTOR. |
3.12.1. Creating a Backup Shipping Schedule
You create a backup shipping schedule by using the LINSTOR client schedule create
command and
defining the frequency of backup shipping using cron
syntax. You also need to set options
that name the schedule and define various aspects of the backup shipping, such as on-failure
actions, the number of local and remote backup copies to keep, and whether to also schedule
incremental backup shipping.
At a minimum, the command needs a schedule name and a full backup cron schema to create a backup shipping schedule. An example command would look like this:
# linstor schedule create \ --incremental-cron '* * * * *' \ (1) --keep-local 5 \ (2) --keep-remote 4 \ (3) --on-failure RETRY \ (4) --max-retries 10 \ (5) <schedule_name> \ (6) '* * * * *' # full backup cron schema (7)
Enclose cron schemas within single or double quotation marks. |
1 | If specified, the incremental cron schema describes how frequently to create and ship incremental backups. New incremental backups are based on the most recent full backup. |
2 | The --keep-local option allows you to specify how many snapshots that a full backup is
based upon should be kept at the local backup source. If unspecified, all snapshots will be
kept. [OPTIONAL] |
3 | The --keep-remote option allows you to specify how many full backups should be kept at the
remote destination. This option only works with S3 remote backup destinations, because you would
not want to allow a cluster node to delete backups from a node in another cluster. All
incremental backups based on a deleted full backup will also be deleted at the remote
destination. If unspecified, the --keep-remote option defaults to “all”. [OPTIONAL] |
4 | Specifies whether to “RETRY” or “SKIP” the scheduled backup shipping if it fails. If “SKIP”
is specified, LINSTOR will ignore the failure and continue with the next scheduled backup
shipping. If “RETRY” is specified, LINSTOR will wait 60 seconds and then try the backup shipping
again. The LINSTOR schedule create command defaults to “SKIP” if no --on-failure option is
given. [OPTIONAL] |
5 | The number of times to retry the backup shipping if a scheduled backup shipping fails and
the --on-failure RETRY option has been given. Without this option, the LINSTOR controller will
retry the scheduled backup shipping indefinitely, until it is successful. [OPTIONAL] |
6 | The name that you give the backup schedule so that you can reference it later with the schedule list, modify, delete, enable, or disable commands. [REQUIRED] |
7 | This cron schema describes how frequently LINSTOR creates snapshots and ships full backups. |
If you specify an incremental cron schema that has overlap with the full cron schema that you specify, at the times when both types of backup shipping would occur simultaneously, LINSTOR will only make and ship a full backup. For example, if you specify that a full backup be made every three hours, and an incremental backup be made every hour, then every third hour, LINSTOR will only make and ship a full backup. For this reason, specifying the same cron schema for both your incremental and full backup shipping schedules would be useless, because incremental backups will never be made. |
3.12.2. Modifying a Backup Shipping Schedule
You can modify a backup shipping schedule by using the LINSTOR client schedule modify
command.
The syntax for the command is the same as that for the schedule create
command. The name that
you specify with the schedule modify
command must be an already existing backup schedule. Any
options to the command that you do not specify will retain their existing values. If you want to
set the keep-local
or keep-remote
options back to their default values, you can set them to
“all”. If you want to set the max-retries
option to its default value, you can set it to
“forever”.
3.12.3. Configuring the Number of Local Snapshots and Remote Backups to Keep
Your physical storage is not infinite and your remote storage has a cost, so you will likely want to set limits on the number of snapshots and backups you keep.
Both the --keep-remote
and --keep-local
options deserve special mention as they have
implications beyond what may be obvious. Using these options, you specify how many snapshots or
full backups should be kept, either on the local source or the remote destination.
Configuring the Keep-local Option
For example, if a --keep-local=2
option is set, then the backup shipping schedule, on first
run, will make a snapshot for a full backup. On the next scheduled full backup shipping, it will
make a second snapshot for a full backup. On the next scheduled full backup shipping, it makes a
third snapshot for a full backup. This time, however, after successful completion, LINSTOR
deletes the first (oldest) full backup shipping snapshot. If snapshots were made for any
incremental backups based on this full snapshot, they will also be deleted from the local source
node. On the next successful full backup shipping, LINSTOR will delete the second full backup
snapshot and any incremental snapshots based upon it, and so on, with each successive backup
shipping.
If there are local snapshots remaining from failed shipments, these will be deleted first, even if they were created later. |
If you have enabled a backup shipping schedule and then later manually delete a LINSTOR snapshot, LINSTOR may not be able to delete everything it was supposed to. For example, if you delete a full backup snapshot definition, on a later full backup scheduled shipping, there may be incremental snapshots based on the manually deleted full backup snapshot that will not be deleted.
Configuring the Keep-remote Option
As mentioned in the callouts for the example linstor schedule create
command above, the
keep-remote
option only works for S3 remote destinations. Here is an example of how the
option works. If a --keep-remote=2
option is set, then the backup shipping schedule, on first
run, will make a snapshot for a full backup and ship it to the remote destination. On the next
scheduled full backup shipping, a second snapshot is made and a full backup shipped to the
remote destination. On the next scheduled full backup shipping, a third snapshot is made and a
full backup shipped to the remote destination. This time, additionally, after the third snapshot
successfully ships, the first full backup is deleted from the remote destination. If any
incremental backups were scheduled and made between the full backups, any that were made from
the first full backup would be deleted along with the full backup.
This option only deletes backups at the remote destination. It does not delete snapshots that the full backups were based upon at the local source node. |
3.12.4. Listing a Backup Shipping Schedule
You can list your backup shipping schedules by using the linstor schedule list
command.
For example:
# linstor schedule list ╭──────────────────────────────────────────────────────────────────────────────────────╮ ┊ Name ┊ Full ┊ Incremental ┊ KeepLocal ┊ KeepRemote ┊ OnFailure ┊ ╞══════════════════════════════════════════════════════════════════════════════════════╡ ┊ my-bu-schedule ┊ 2 * * * * ┊ ┊ 3 ┊ 2 ┊ SKIP ┊ ╰──────────────────────────────────────────────────────────────────────────────────────╯
3.12.5. Deleting a Backup Shipping Schedule
The LINSTOR client schedule delete
command completely deletes a backup shipping schedule
LINSTOR object. The command’s only argument is the schedule name that you want to delete. If the
deleted schedule is currently creating or shipping a backup, the scheduled shipping process is
stopped. Depending on at which point the process stops, a snapshot, or a backup, or both, might
not be created and shipped.
This command does not affect previously created snapshots or successfully shipped backups. These will be retained until they are manually deleted.
3.12.6. Enabling Scheduled Backup Shipping
You can use the LINSTOR client backup schedule enable
command to enable a previously created
backup shipping schedule. The command has the following syntax:
# linstor backup schedule enable \ [--node source_node] \ (1) [--rg resource_group_name | --rd resource_definition_name] \ (2) remote_name \ (3) schedule_name (4)
1 | This is a special option that allows you to specify the controller node that will be used as a source for scheduled backup shipments, if possible. If you omit this option from the command, then LINSTOR will choose a source node at the time a scheduled shipping is made. [OPTIONAL] |
2 | You can set here either the resource group or the resource definition (but not both) that you want to enable the backup shipping schedule for. If you omit this option from the command, then the command enables scheduled backup shipping for all deployed LINSTOR resources that can make snapshots. [OPTIONAL] |
3 | The name of the remote destination that you want to ship backups to. [REQUIRED] |
4 | The name of a previously created backup shipping schedule. [REQUIRED] |
3.12.7. Disabling a Backup Shipping Schedule
To disable a previously enabled backup shipping schedule, you use the LINSTOR client backup
schedule disable
command. The command has the following syntax:
# linstor backup schedule disable \ [--rg resource_group_name | --rd resource_definition_name] \ remote_name \ (3) schedule_name (4)
If you include the option specifying either a resource group or resource definition, as
described in the backup schedule enable
command example above, then you disable the schedule
only for that resource group or resource definition.
For example, if you omitted specifying a resource group or resource definition in an earlier
backup schedule enable
command, LINSTOR would schedule backup shipping for all its deployed
resources that can make snapshots. Your disable command would then only affect the resource
group or resource definition that you specify with the command. The backup shipping schedule
would still apply to any deployed LINSTOR resources besides the specified resource group or
resource definition.
The same as for the backup schedule enable
command, if you specify neither a resource group
nor a resource definition, then LINSTOR disables the backup shipping schedule at the controller
level for all deployed LINSTOR resources.
3.12.8. Deleting Aspects of a Backup Shipping Schedule
You can use the linstor backup schedule delete
command to granularly delete either a specified
resource definition or a resource group from a backup shipping schedule, without deleting the
schedule itself. This command has the same syntax and arguments as the backup schedule disable
command. If you specify neither a resource group nor a resource definition, the backup shipping
schedule you specify will be deleted at the controller level.
It may be helpful to think about the backup schedule delete
command as a way that you can
remove a backup shipping schedule-remote pair from a specified LINSTOR object level, either a
resource definition, a resource group, or at the controller level if neither is specified.
The backup schedule delete
command does not affect previously created snapshots or
successfully shipped backups. These will be retained until they are manually deleted, or until
they are removed by the effects of a still applicable keep-local or keep-remote option.
You might want to use this command when you have disabled a backup schedule for multiple LINSTOR
object levels and later want to affect a granular change, where a backup schedule enable
command might have unintended consequences.
For example, consider a scenario where you have a backup schedule-remote pair that you enabled at a controller level. This controller has a resource group, myresgroup that has several resource definitions, resdef1 through resdef9, under it. For maintenance reasons perhaps, you disable the schedule for two resource definitions, resdef1 and resdef2. You then realize that further maintenance requires that you disable the backup shipping schedule at the resource group level, for your myresgroup resource group.
After completing some maintenance, you are able to enable the backup shipping schedule for
resdef3 through resdef9, but you are not yet ready to resume (enable) backup shipping for
resdef1 and resdef2. You can enable backup shipping for each resource definition
individually, resdef3 through resdef9, or you can use the backup schedule delete
command
to delete the backup shipping schedule from the resource group, myresgroup. If you use the
backup schedule delete
command, backups of resdef3 through resdef9 will ship again because
the backup shipping schedule is enabled at the controller level, but resdef1 and resdef2
will not ship because the backup shipping schedule is still disabled for them at the resource
definition level.
When you complete your maintenance and are again ready to ship backups for resdef1 and resdef2, you can delete the backup shipping schedule for those two resource definitions to return to your starting state: backup shipping scheduled for all LINSTOR deployed resources at the controller level. To visualize this it may be helpful to refer to the decision tree diagram for how LINSTOR decides whether or not to ship a backup in the How the LINSTOR Controller Determines Scheduled Backup Shipping subsection.
In the example scenario above, you might have enabled backup shipping on the resource
group, after completing some maintenance. In this case, backup shipping would resume for
resource definitions resdef3 through resdef9 but continue not to ship for resource
definitions resdef1 and resdef2 because backup shipping was still disabled for those
resource definitions. After you completed all maintenance, you could delete the backup shipping
schedule on resdef1 and resdef2. Then all of your resource definitions would be shipping
backups, as they were prior to your maintenance, because the schedule-remote pair was enabled at
the resource group level. However, this would remove your option to globally stop all scheduled
shipping at some later point in time at the controller level because the enabled schedule at the
resource group level would override any schedule disable command applied at the controller
level.
|
3.12.9. Listing Backup Shipping Schedules by Resource
You can list backup schedules by resource, using the LINSTOR client schedule list-by-resource
command. This command will show LINSTOR resources and how any backup shipping schedules apply
and to which remotes they are being shipped. If resources are not being shipped then the command
will show:
-
Whether resources have no schedule-remote-pair entries (empty cells)
-
Whether they have schedule-remote-pair entries but they are disabled (“disabled”)
-
Whether they have no resources, so no backup shipments can be made, regardless of whether any schedule-remote-pair entries are enabled or not (“undeployed”)
If resources have schedule-remote-pairs and are being shipped, the command output will show when the last backup was shipped and when the next backup is scheduled to ship. It will also show whether the next and last backup shipments were full or incremental backups. Finally, the command will show when the next planned incremental (if any) and full backup shipping will occur.
You can use the --active-only
flag with the schedule list-by-resource
command to filter out all resources that are not being shipped.
3.12.10. How the LINSTOR Controller Determines Scheduled Backup Shipping
To determine if the LINSTOR Controller will ship a deployed LINSTOR resource with a certain backup schedule for a given remote destination, the LINSTOR Controller uses the following logic:
As the diagram shows, enabled or disabled backup shipping schedules have effect in the following order:
-
Resource definition level
-
Resource group level
-
Controller level
A backup shipping schedule-remote pair that is enabled or disabled at a preceding level will override the enabled or disabled status for the same schedule-remote pair at a later level.
3.12.11. Determining How Scheduled Backup Shipping Affects a Resource
To determine how a LINSTOR resource will be affected by scheduled backup shipping, you can use
the LINSTOR client schedule list-by-resource-details
command for a specified LINSTOR resource.
The command will output a table that shows on what LINSTOR object level a backup shipping schedule is either not set (empty cell), enabled, or disabled.
By using this command, you can determine on which level you need to make a change to enable, disable, or delete scheduled backup shipping for a resource.
Example output could look like this:
# linstor schedule list-by-resource-details my_linstor_resource_name ╭───────────────────────────────────────────────────────────────────────────╮ ┊ Remote ┊ Schedule ┊ Resource-Definition ┊ Resource-Group ┊ Controller ┊ ╞═══════════════════════════════════════════════════════════════════════════╡ ┊ rem1 ┊ sch1 ┊ Disabled ┊ ┊ Enabled ┊ ┊ rem1 ┊ sch2 ┊ ┊ Enabled ┊ ┊ ┊ rem2 ┊ sch1 ┊ Enabled ┊ ┊ ┊ ┊ rem2 ┊ sch5 ┊ ┊ Enabled ┊ ┊ ┊ rem3 ┊ sch4 ┊ ┊ Disabled ┊ Enabled ┊ ╰───────────────────────────────────────────────────────────────────────────╯
3.13. Setting DRBD Options for LINSTOR Objects
You can use LINSTOR commands to set DRBD options. Configurations in files that are not managed
by LINSTOR, such as /etc/drbd.d/global_common.conf
, will be ignored. The syntax for this
command is generally:
# linstor <LINSTOR_object> drbd-options --<DRBD_option> <value> <LINSTOR_object_identifiers>
In the syntax above, <LINSTOR_ object_identifiers>
is a placeholder for identifiers such as a
node name, node names, or a resource name, or a combination of these identifiers.
For example, to set the DRBD replication protocol for a resource definition named backups
,
enter:
# linstor resource-definition drbd-options --protocol C backups
You can enter a LINSTOR object along with drbd-options
and the --help
, or -h
, flag to
show the command usage, available options, and the default value for each option. For example:
# linstor controller drbd-options -h
3.13.1. Setting DRBD Peer Options for LINSTOR Resources or Resource Connections
The LINSTOR resource object is an exception to the general syntax for setting DRBD options for
LINSTOR objects. With the LINSTOR resource object, you can use the drbd-peer-options
to set
DRBD options at the connection level between the two nodes that you specify. Specifying
drbd-peer-options
for a LINSTOR resource object between two nodes is equivalent to using
the`linstor resource-connection drbd-peer-options` for a resource between two nodes.
For example, to set the DRBD maximum buffer size to 8192 at a connection level, for a resource
named backups
, between two nodes, node-0
and node-1
, enter:
# linstor resource drbd-peer-options --max-buffers 8192 node-0 node-1 backups
The command above is equivalent to the following:
# linstor resource-connection drbd-peer-options --max-buffers 8192 node-0 node-1 backups
Indeed, when using the linstor --curl
command to examine the two commands actions on the
LINSTOR REST API, the output is identical:
# linstor --curl resource drbd-peer-options --max-buffers 8192 node-0 node-1 backups curl -X PUT -H "Content-Type: application/json" -d '{"override_props": {"DrbdOptions/Net/max-buffers": "8192"}}' http://localhost:3370/v1/resource-definitions/backups/resource-connections/node-0/node-1 # linstor --curl resource-connection drbd-peer-options --max-buffers 8192 node-0 node-1 backups curl -X PUT -H "Content-Type: application/json" -d '{"override_props": {"DrbdOptions/Net/max-buffers": "8192"}}' http://localhost:3370/v1/resource-definitions/backups/resource-connections/node-0/node-1
The connection section of the LINSTOR-generated resource file backups.res
on node-0
will
look something like this:
connection { _peer_node_id 1; path { _this_host ipv4 192.168.222.10:7000; _remote_host ipv4 192.168.222.11:7000; } path { _this_host ipv4 192.168.121.46:7000; _remote_host ipv4 192.168.121.220:7000; } net { [...] max-buffers 8192; _name "node-1"; } }
If there are multiple paths between the two nodes, as in the example above, DRBD options
that you set using the resource drbd-peer-options command will apply to all of them.
|
3.13.2. Setting DRBD Options for Node Connections
You can use the drbd-peer-options
argument to set DRBD options at a connection level, between
two nodes, for example:
# linstor node-connection drbd-peer-options --ping-timeout 299 node-0 node-1
The preceding command would set the DRBD ping-timeout
option to 29.9 seconds at a connection
level between two nodes, node-0
and node-1
.
3.13.3. Verifying Options for LINSTOR Objects
You can verify a LINSTOR object’s set properties by using the list-properties
command, for example:
# linstor resource-definition list-properties backups +------------------------------------------------------+ | Key | Value | |======================================================| | DrbdOptions/Net/protocol | C | [...]
3.13.4. Removing DRBD Options from LINSTOR Objects
To remove a previously set DRBD option, prefix the option name with unset-
. For
example:
# linstor resource-definition drbd-options --unset-protocol backups
The same syntax applies to any drbd-peer-options
set either on a LINSTOR resource, resource
connection, or node connection. For example:
# linstor resource-connection drbd-peer-options --unset-max-buffers node-0 node-1 backups
Removing a DRBD option or DRBD peer option will return the option to its default value. Refer to
the linstor <LINSTOR_object> drbd-options --help
(or drbd-peer-options --help
) command
output for the default values of options. You can also refer to the drbd.conf-9.0
man page to
get information about DRBD options.
3.14. Adding and Removing Disks
LINSTOR can convert resources between diskless and having a disk.
This is achieved with the resource toggle-disk
command,
which has syntax similar to resource create
.
For instance, add a disk to the diskless resource backups
on ‘alpha’:
# linstor resource toggle-disk alpha backups --storage-pool pool_ssd
Remove this disk again:
# linstor resource toggle-disk alpha backups --diskless
3.14.1. Migrating Disks Between Nodes
To move a resource between nodes without reducing redundancy at any point,
LINSTOR’s disk migrate feature can be used.
First create a diskless resource on the target node,
and then add a disk using the --migrate-from
option.
This will wait until the data has been synced to the new disk and then remove
the source disk.
For example, to migrate a resource backups
from ‘alpha’ to ‘bravo’:
# linstor resource create bravo backups --drbd-diskless # linstor resource toggle-disk bravo backups --storage-pool pool_ssd --migrate-from alpha
3.15. Configuring DRBD Proxy Using LINSTOR
LINSTOR expects DRBD Proxy to be running on the nodes which are involved in the relevant connections. It does not currently support connections through DRBD Proxy on a separate node.
Suppose our cluster consists of nodes ‘alpha’ and ‘bravo’ in a local network
and ‘charlie’ at a remote site, with a resource definition named backups
deployed to each of the nodes. Then DRBD Proxy can be enabled for the
connections to ‘charlie’ as follows:
# linstor drbd-proxy enable alpha charlie backups # linstor drbd-proxy enable bravo charlie backups
The DRBD Proxy configuration can be tailored with commands such as:
# linstor drbd-proxy options backups --memlimit 100000000 # linstor drbd-proxy compression zlib backups --level 9
LINSTOR does not automatically optimize the DRBD configuration for long-distance replication, so you will probably want to set some configuration options such as the protocol:
# linstor resource-connection drbd-options alpha charlie backups --protocol A # linstor resource-connection drbd-options bravo charlie backups --protocol A
Please contact LINBIT for assistance optimizing your configuration.
3.15.1. Automatically Enabling DRBD Proxy
LINSTOR can also be configured to automatically enable the above mentioned Proxy connection between two nodes. For this automation, LINSTOR first needs to know on which site each node is.
# linstor node set-property alpha Site A # linstor node set-property bravo Site A # linstor node set-property charlie Site B
As the Site
property might also be used for other site-based decisions in
future features, the DrbdProxy/AutoEnable
also has to be set to true
:
# linstor controller set-property DrbdProxy/AutoEnable true
This property can also be set on node, resource-definition, resource and resource-connection level (from left to right in increasing priority, whereas the controller is the left-most, that is, the least prioritized level).
Once this initialization steps are completed, every newly created resource will automatically check if it has to enable DRBD proxy to any of its peer-resources.
3.16. External Database Providers
It is possible to have LINSTOR working with an external database provider like PostgreSQL, MariaDB and since version 1.1.0 even etcd key value store is supported.
To use an external database there are a few additional steps to configure.
You have to create a DB/Schema and user to use for linstor, and configure this in the
/etc/linstor/linstor.toml
.
3.16.1. PostgreSQL
A sample PostgreSQL linstor.toml
looks like this:
[db] user = "linstor" password = "linstor" connection_url = "jdbc:postgresql://localhost/linstor"
3.16.2. MariaDB and MySQL
A sample MariaDB linstor.toml
looks like this:
[db] user = "linstor" password = "linstor" connection_url = "jdbc:mariadb://localhost/LINSTOR?createDatabaseIfNotExist=true"
The LINSTOR schema/database is created as LINSTOR so verify that the MariaDB connection string refers to the LINSTOR schema, as in the example above.
|
3.16.3. etcd
etcd is a distributed key-value store that makes it easy to keep your LINSTOR database distributed in a HA-setup.
The etcd driver is already included in the LINSTOR-controller package and only needs to be configured in the linstor.toml
.
More information about how to install and configure etcd can be found here: etcd docs
And here is a sample [db] section from the linstor.toml
:
[db] ## only set user/password if you want to use authentication, only since LINSTOR 1.2.1 # user = "linstor" # password = "linstor" ## for etcd ## do not set user field if no authentication required connection_url = "etcd://etcdhost1:2379,etcdhost2:2379,etcdhost3:2379" ## if you want to use TLS, only since LINSTOR 1.2.1 # ca_certificate = "ca.pem" # client_certificate = "client.pem" ## if you want to use client TLS authentication too, only since LINSTOR 1.2.1 # client_key_pkcs8_pem = "client-key.pkcs8" ## set client_key_password if private key has a password # client_key_password = "mysecret"
3.17. Configuring the LINSTOR Controller
The LINSTOR Controller has a configuration file that is and has to be placed into the following path: /etc/linstor/linstor.toml
.
A recent configuration example can be found here: linstor.toml-example
3.17.1. LINSTOR REST API
To make LINSTOR’s administrative tasks more accessible and also available for web-frontends a
REST API has been created. The REST API is embedded in the linstor-controller
and since LINSTOR 0.9.13 configured through the linstor.toml
configuration file.
[http] enabled = true port = 3370 listen_addr = "127.0.0.1" # to disable remote access
If you want to use the REST API the current documentation can be found on the following link: https://app.swaggerhub.com/apis-docs/Linstor/Linstor/
3.17.2. LINSTOR REST API HTTPS
The HTTP REST API can also run secured by HTTPS and is highly recommended if you use any features that require authorization. To do so you have to create a Java keystore file with a valid certificate that will be used to encrypt all HTTPS traffic.
Here is a simple example on how you can create a self signed certificate with the keytool
that is included
in the Java Runtime:
keytool -keyalg rsa -keysize 2048 -genkey -keystore ./keystore_linstor.jks\ -alias linstor_controller\ -dname "CN=localhost, OU=SecureUnit, O=ExampleOrg, L=Vienna, ST=Austria, C=AT"
keytool
will ask for a password to secure the generated keystore file and is needed for the
LINSTOR Controller configuration.
In your linstor.toml
file you have to add the following section:
[https] keystore = "/path/to/keystore_linstor.jks" keystore_password = "linstor"
Now (re)start the linstor-controller
and the HTTPS REST API should be available on port 3371.
More information about how to import other certificates can be found here: https://docs.oracle.com/javase/8/docs/technotes/tools/unix/keytool.html
When HTTPS is enabled, all requests to the HTTP /v1/ REST API will be redirected to the HTTPS redirect. |
LINSTOR REST API HTTPS Restricted Client Access
Client access can be restricted by using a SSL/TLS truststore on the Controller. Basically you create a certificate for your client and add it to your truststore and the client then uses this certificate for authentication.
First create a client certificate:
keytool -keyalg rsa -keysize 2048 -genkey -keystore client.jks\ -storepass linstor -keypass linstor\ -alias client1\ -dname "CN=Client Cert, OU=client, O=Example, L=Vienna, ST=Austria, C=AT"
Then we import this certificate to our controller truststore:
keytool -importkeystore\ -srcstorepass linstor -deststorepass linstor -keypass linstor\ -srckeystore client.jks -destkeystore trustore_client.jks
And enable the truststore in the linstor.toml
configuration file:
[https] keystore = "/path/to/keystore_linstor.jks" keystore_password = "linstor" truststore = "/path/to/trustore_client.jks" truststore_password = "linstor"
Now restart the Controller and it will no longer be possible to access the controller API without a correct certificate.
The LINSTOR client needs the certificate in PEM format, so before we can use it we have to convert the java keystore certificate to the PEM format.
# Convert to pkcs12 keytool -importkeystore -srckeystore client.jks -destkeystore client.p12\ -storepass linstor -keypass linstor\ -srcalias client1 -srcstoretype jks -deststoretype pkcs12 # use openssl to convert to PEM openssl pkcs12 -in client.p12 -out client_with_pass.pem
To avoid entering the PEM file password all the time it might be convenient to remove the password.
openssl rsa -in client_with_pass.pem -out client1.pem openssl x509 -in client_with_pass.pem >> client1.pem
Now this PEM file can easily be used in the client:
linstor --certfile client1.pem node list
The --certfile
parameter can also added to the client configuration file, see
Using the LINSTOR Client for more details.
3.18. Configuring LINSTOR Satellite
The LINSTOR Satellite software has an optional configuration file that uses the TOML file syntax and has to be put into the following path /etc/linstor/linstor_satellite.toml
.
A recent configuration example can be found here: linstor_satellite.toml-example
3.19. Logging
LINSTOR uses SLF4J with Logback as binding. This gives
LINSTOR the possibility to distinguish between the log levels ERROR
, WARN
, INFO
, DEBUG
and TRACE
(in order of increasing verbosity). The following are
the different ways that you can set the logging level, ordered by priority (first has highest priority):
-
Since LINSTOR client version 1.20.1, you can use the command
controller set-log-level
to change the log level used by LINSTOR’s running configuration. Various arguments can be used with this command. Refer to the command’s--help
text for details. For example, to set the log level toTRACE
on the LINSTOR controller and all satellites, enter the following command:$ linstor controller set-log-level --global TRACE
To change the LINSTOR log level on a particular node, you can use the LINSTOR client (since version 1.20.1) command
node set-log-level
.Changes that you make to the log level by using the LINSTOR client will not persist LINSTOR service restarts, for example, if a node reboots. -
TRACE
mode can beenabled
ordisabled
using the debug console:Command ==> SetTrcMode MODE(enabled) SetTrcMode Set TRACE level logging mode New TRACE level logging mode: ENABLED
-
When starting the controller or satellite a command line argument can be passed:
java ... com.linbit.linstor.core.Controller ... --log-level TRACE java ... com.linbit.linstor.core.Satellite ... --log-level TRACE
-
The recommended place is the
logging
section in the configuration file. The default configuration file location is/etc/linstor/linstor.toml
for the controller and/etc/linstor/linstor_satellite.toml
for the satellite. Configure the logging level as follows:[logging] level="TRACE"
-
As LINSTOR is using Logback as an implementation,
/usr/share/linstor-server/lib/logback.xml
can also be used. Currently only this approach supports different log levels for different components, like shown in the example below:<?xml version="1.0" encoding="UTF-8"?> <configuration scan="false" scanPeriod="60 seconds"> <!-- Values for scanPeriod can be specified in units of milliseconds, seconds, minutes or hours https://logback.qos.ch/manual/configuration.html --> <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> <!-- encoders are assigned the type ch.qos.logback.classic.encoder.PatternLayoutEncoder by default --> <encoder> <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger - %msg%n</pattern> </encoder> </appender> <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender"> <file>${log.directory}/linstor-${log.module}.log</file> <append>true</append> <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder"> <Pattern>%d{yyyy_MM_dd HH:mm:ss.SSS} [%thread] %-5level %logger - %msg%n</Pattern> </encoder> <rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy"> <FileNamePattern>logs/linstor-${log.module}.%i.log.zip</FileNamePattern> <MinIndex>1</MinIndex> <MaxIndex>10</MaxIndex> </rollingPolicy> <triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy"> <MaxFileSize>2MB</MaxFileSize> </triggeringPolicy> </appender> <logger name="LINSTOR/Controller" level="TRACE" additivity="false"> <appender-ref ref="STDOUT" /> <!-- <appender-ref ref="FILE" /> --> </logger> <logger name="LINSTOR/Satellite" level="TRACE" additivity="false"> <appender-ref ref="STDOUT" /> <!-- <appender-ref ref="FILE" /> --> </logger> <root level="WARN"> <appender-ref ref="STDOUT" /> <!-- <appender-ref ref="FILE" /> --> </root> </configuration>
See the Logback Manual to find more details about logback.xml
.
When none of the configuration methods above is used LINSTOR will default to INFO
log level.
3.20. Monitoring
Since LINSTOR 1.8.0, a Prometheus /metrics
HTTP path is provided with LINSTOR and JVM specific
exports.
The /metrics
path also supports three GET arguments to reduce LINSTOR’s reported data:
-
resource
-
storage_pools
-
error_reports
These all default to true
. To disable, for example error report data: http://localhost:3370/metrics?error_reports=false
3.21. Secure Satellite Connections
It is possible to have the LINSTOR use SSL/TLS secure TCP connection between controller and satellite connections.
Without going into further details on how Java’s SSL/TLS engine works we will give you
command line snippets using the keytool
from Java’s runtime environment on how to configure
a three node setup using secure connections.
The node setup looks like this:
Node alpha
is the just the controller.
Node bravo
and node charlie
are just satellites.
Here are the commands to generate such a keystore setup, values should of course be edited for your environment.
# create directories to hold the key files mkdir -p /tmp/linstor-ssl cd /tmp/linstor-ssl mkdir alpha bravo charlie # create private keys for all nodes keytool -keyalg rsa -keysize 2048 -genkey -keystore alpha/keystore.jks\ -storepass linstor -keypass linstor\ -alias alpha\ -dname "CN=Max Mustermann, OU=alpha, O=Example, L=Vienna, ST=Austria, C=AT" keytool -keyalg rsa -keysize 2048 -genkey -keystore bravo/keystore.jks\ -storepass linstor -keypass linstor\ -alias bravo\ -dname "CN=Max Mustermann, OU=bravo, O=Example, L=Vienna, ST=Austria, C=AT" keytool -keyalg rsa -keysize 2048 -genkey -keystore charlie/keystore.jks\ -storepass linstor -keypass linstor\ -alias charlie\ -dname "CN=Max Mustermann, OU=charlie, O=Example, L=Vienna, ST=Austria, C=AT" # import truststore certificates for alpha (needs all satellite certificates) keytool -importkeystore\ -srcstorepass linstor -deststorepass linstor -keypass linstor\ -srckeystore bravo/keystore.jks -destkeystore alpha/certificates.jks keytool -importkeystore\ -srcstorepass linstor -deststorepass linstor -keypass linstor\ -srckeystore charlie/keystore.jks -destkeystore alpha/certificates.jks # import controller certificate into satellite truststores keytool -importkeystore\ -srcstorepass linstor -deststorepass linstor -keypass linstor\ -srckeystore alpha/keystore.jks -destkeystore bravo/certificates.jks keytool -importkeystore\ -srcstorepass linstor -deststorepass linstor -keypass linstor\ -srckeystore alpha/keystore.jks -destkeystore charlie/certificates.jks # now copy the keystore files to their host destinations ssh root@alpha mkdir /etc/linstor/ssl scp alpha/* root@alpha:/etc/linstor/ssl/ ssh root@bravo mkdir /etc/linstor/ssl scp bravo/* root@bravo:/etc/linstor/ssl/ ssh root@charlie mkdir /etc/linstor/ssl scp charlie/* root@charlie:/etc/linstor/ssl/ # generate the satellite ssl config entry echo '[netcom] type="ssl" port=3367 server_certificate="ssl/keystore.jks" trusted_certificates="ssl/certificates.jks" key_password="linstor" keystore_password="linstor" truststore_password="linstor" ssl_protocol="TLSv1.2" ' | ssh root@bravo "cat > /etc/linstor/linstor_satellite.toml" echo '[netcom] type="ssl" port=3367 server_certificate="ssl/keystore.jks" trusted_certificates="ssl/certificates.jks" key_password="linstor" keystore_password="linstor" truststore_password="linstor" ssl_protocol="TLSv1.2" ' | ssh root@charlie "cat > /etc/linstor/linstor_satellite.toml"
Now just start controller and satellites and add the nodes with --communication-type SSL
.
3.22. Configuring LDAP Authentication
You can configure LINSTOR to use LDAP authentication to limit access to the LINSTOR Controller.
This feature is disabled by default but you can enable and configure it by editing the
LINSTOR configuration TOML file. After editing the configuration file, you will need to restart
the linstor-controller.service
. An example LDAP section within the configuration file looks
like this:
[ldap] enabled = true (1) # allow_public_access: if no authorization fields are given allow # users to work with the public context allow_public_access = false (2) # uniform resource identifier: LDAP URI to use # for example, "ldaps://hostname" (LDAPS) or "ldap://hostname" (LDAP) uri = "ldaps://ldap.example.com" # distinguished name: {user} can be used as template for the user name dn = "uid={user}" (3) # search base for the search_filter field search_base = "dc=example,dc=com" (4) # search_filter: ldap filter to restrict users on memberships search_filter = "(&(uid={user})(memberof=ou=storage-services,dc=example,dc=com))" (5)
1 | enabled is a Boolean value. Authentication is disabled by default. |
2 | allow_public_access is a Boolean value. If set to true, and LDAP authentication is
enabled, then users will be allowed to work with the LINSTOR Controller’s public context. If
set to false and LDAP authentication is enabled, then users without LDAP authenticating
credentials will be unable to access the LINSTOR Controller for all but the most trivial tasks,
such as displaying version or help information. |
3 | dn is a string value where you can specify the LDAP distiguished name to query the LDAP
directory. Besides the user ID (uid ), the string may consist of other distinguished name
attributes, for example:
dn = "uid={user},ou=storage-services,o=ha,dc=example" |
4 | search_base is a string value where you can specify the starting point in the LDAP
directory tree for the authentication query, for example:
search_base = "ou=storage-services" |
5 | search_filter is a string value where you can specify an LDAP object restriction for
authentication, such as user and group membership, for example:
search_filter = "(&(uid={user})(memberof=ou=storage-services,dc=example,dc=com))" |
It is highly recommended that you configure LINSTOR REST API HTTPS and LDAPS to protect potentially sensitive traffic passing between the LINSTOR Controller and an LDAP server. |
3.22.1. Running LINSTOR Commands as an Authenticated User
After configuring the LINSTOR Controller to authenticate users through LDAP (or LDAPS), and the LINSTOR REST API HTTPS, you will need to enter LINSTOR commands as follows:
$ linstor --user <LDAP_user_name> <command>
If you have configured LDAP authentication without also configuring LINSTOR REST API
HTTPS, you will need to explicitly enable password authentication over HTTP, by using the --allow-insecure-path
flag with your linstor
commands. This is not recommended outside of a secured and isolated LAN, as you will be sending credentials in plain text.
$ linstor --allow-insecure-auth --user <LDAP_user_name> <command>
The LINSTOR Controller will prompt you for the user’s password, in each of the above examples. You may optionally use the --password
argument to supply the user’s password on the command line, with all the warnings of caution that would go along with doing so.
3.23. Automatisms for DRBD Resources
This section details some of LINSTOR’s automatisms for DRBD resources.
3.23.1. Auto-Quorum Policies
LINSTOR automatically configures quorum policies on resources when quorum is achievable. This means, whenever you have at least two diskful and one or more diskless resource assignments, or three or more diskful resource assignments, LINSTOR will enable quorum policies for your resources automatically.
Inversely, LINSTOR will automatically disable quorum policies whenever there are less than the minimum required resource assignments to achieve quorum.
This is controlled through the, DrbdOptions/auto-quorum
, property which
can be applied to the linstor-controller, resource-group, and
resource-definition. Accepted values for the
DrbdOptions/auto-quorum
property are disabled
, suspend-io
, and
io-error
.
Setting the DrbdOptions/auto-quorum
property to disabled
will
allow you to manually, or more granularly, control the quorum policies
of your resources should you want to.
The default policies for DrbdOptions/auto-quorum are quorum
majority , and on-no-quorum io-error . For more information about DRBD’s
quorum features and their behavior, please refer to the
quorum section of the DRBD user’s guide.
|
The DrbdOptions/auto-quorum policies will override any
manually configured properties if DrbdOptions/auto-quorum is not disabled.
|
For example, to manually set the quorum policies of a resource-group
named my_ssd_group
, you would use the following commands:
# linstor resource-group set-property my_ssd_group DrbdOptions/auto-quorum disabled # linstor resource-group set-property my_ssd_group DrbdOptions/Resource/quorum majority # linstor resource-group set-property my_ssd_group DrbdOptions/Resource/on-no-quorum suspend-io
You may want to disable DRBD’s quorum features completely. To do that,
you would need to first disable DrbdOptions/auto-quorum
on the
appropriate LINSTOR object, and then set the DRBD quorum features
accordingly. For example, use the following commands to disable quorum
entirely on the my_ssd_group
resource-group:
# linstor resource-group set-property my_ssd_group DrbdOptions/auto-quorum disabled # linstor resource-group set-property my_ssd_group DrbdOptions/Resource/quorum off # linstor resource-group set-property my_ssd_group DrbdOptions/Resource/on-no-quorum
Setting DrbdOptions/Resource/on-no-quorum to an empty value
in the commands above deletes the property from the object entirely.
|
3.23.2. Auto-Evict
If a satellite is offline for a prolonged period of time, LINSTOR can be configured to declare that node as evicted. This triggers an automated reassignment of the affected DRBD resources to other nodes to ensure a minimum replica count is kept.
This feature uses the following properties to adapt the behaviour.
-
DrbdOptions/AutoEvictMinReplicaCount
sets the number of replicas that should always be present. You can set this property on the controller to change a global default, or on a specific resource-definition or resource-group to change it only for that resource-definition or resource-group. If this property is left empty, the place-count set for the auto-placer of the corresponding resource-group will be used. -
DrbdOptions/AutoEvictAfterTime
describes how long a node can be offline in minutes before the eviction is triggered. You can set this property on the controller to change a global default, or on a single node to give it a different behavior. The default value for this property is 60 minutes. -
DrbdOptions/AutoEvictMaxDisconnectedNodes
sets the percentage of nodes that can be not reachable (for whatever reason) at the same time. If more than the given percent of nodes are offline at the same time, the auto-evict will not be triggered for any node , since in this case LINSTOR assumes connection problems from the controller. This property can only be set for the controller, and only accepts a value between 0 and 100. The default value is 34. If you want to turn the auto-evict-feature off, simply set this property to 0. If you want to always trigger the auto-evict, regardless of how many satellites are unreachable, set it to 100. -
DrbdOptions/AutoEvictAllowEviction
is an additional property that can stop a node from being evicted. This can be useful for various cases, for example if you need to shut down a node for maintenance. You can set this property on the controller to change a global default, or on a single node to give it a different behavior. It accepts true and false as values and per default is set to true on the controller. You can use this property to turn the auto-evict feature off by setting it to false on the controller, although this might not work completely if you already set different values for individual nodes, since those values take precedence over the global default.
After the linstor-controller loses the connection to a satellite, aside from trying to
reconnect, it starts a timer for that satellite. As soon as that timer exceeds
DrbdOptions/AutoEvictAfterTime
and all of the DRBD-connections to the DRBD-resources
on that satellite are broken, the controller will check whether or not
DrbdOptions/AutoEvictMaxDisconnectedNodes
has been met. If it hasn’t, and
DrbdOptions/AutoEvictAllowEviction
is true for the node in question, the satellite
will be marked as EVICTED. At the same time, the controller will check for every DRBD-resource whether
the number of resources is still above DrbdOptions/AutoEvictMinReplicaCount
. If it is,
the resource in question will be marked as DELETED. If it isn’t, an auto-place with the settings
from the corresponding resource-group will be started. Should the auto-place fail, the
controller will try again later when changes that might allow a different result, such
as adding a new node, have happened. Resources where an auto-place is necessary will only be
marked as DELETED if the corresponding auto-place was successful.
The evicted satellite itself will not be able to reestablish connection with the controller. Even if the node is up and running, a manual reconnect will fail. It is also not possible to delete the satellite, even if it is working as it should be. The satellite can, however, be restored. This will remove the EVICTED-flag from the satellite and allow you to use it again. Previously configured network interfaces, storage pools, properties and similar entities as well as non-DRBD-related resources and resources that could not be autoplaced somewhere else will still be on the satellite. To restore a satellite, use
# linstor node restore [nodename]
Should you want to instead throw everything that once was on that node, including the node
itself, away, you need to use the node lost
command instead.
3.23.3. Auto-Diskful and Related Options
You can set the LINSTOR auto-diskful
and auto-diskful-allow-cleanup
properties for various
LINSTOR objects, for example, a resource definition, to have LINSTOR help automatically make
a Diskless node Diskful and perform appropriate cleanup actions afterwards.
This is useful when a Diskless node has been in a Primary state for a DRBD resource for more than a specified number of minutes. This could happen in cases where you integrate LINSTOR managed storage with other orchestrating and scheduling platforms, such as OpenStack, OpenNebula, and others. On some platforms that you integrate LINSTOR with, you might not have a way to influence where in your cluster a storage volume will be used.
The auto-diskful options give you a way to use LINSTOR to sensibly delegate the roles of your storage nodes in response to an integrated platform’s actions that are beyond your control.
Setting the Auto-Diskful Option
By setting the DrbdOptions/auto-diskful
option on a LINSTOR resource definition , you are
configuring the LINSTOR controller to make a Diskless DRBD resource Diskful if the resource
has been in a DRBD Primary state for more than the specified number of minutes. After the
specified number of minutes, LINSTOR will automatically use the
resource toggle-disk
command to toggle the resource state on the
Diskless node, for the given resource.
To set this property, for example, on a LINSTOR resource definition named myres
with a
threshold of five minutes, enter the command:
# linstor resource-definition set-property myres DrbdOptions/auto-diskful 5
Setting the Auto-Diskful Option on a Resource Group or Controller
You can also set the DrbdOptions/auto-diskful
option on LINSTOR controller
or
resource-group
objects. By setting the option at the controller level, the option will affect
all LINSTOR resource definitions in your LINSTOR cluster that do not have this option set,
either on the resource definition itself, or else on the resource group that you might have
created the resource from.
Setting the option on a LINSTOR resource group will affect all resource definitions that are spawned from the group, unless a resource definition has the option set on it.
The order of priority, from highest to lowest, for the effect of setting the auto-diskful
option is:
-
Resource definition
-
Resource group
-
Controller
Unsetting the Auto-Diskful Option
To unset the LINSTOR auto-diskful
option, enter:
# linstor <controller|resource-definition|resource-group> set-property DrbdOptions/auto-diskful
Setting the Auto-Diskful-Allow-Cleanup Option
A companion option to the LINSTOR auto-diskful
option is the
DrbdOptions/auto-diskful-allow-cleanup
option.
You can set this option on the following LINSTOR objects: node, resource, resource definition,
or resource group. The default value for this option is True
, but the option has no effect
unless the auto-diskful
option has also been set.
After LINSTOR has toggled a resource to Diskful, because the threshold number of minutes has
passed where a Diskless node was in the Primary role for a resource, and after DRBD has
synchronized the data to this previously Diskless and now Primary node, LINSTOR will remove the resource from any Secondary
nodes when that action is necessary to fulfill a replica count constraint that the resource
might have. This could be the case, for example, if you have specified a number of replicas for
a resource by using the --auto-place
option.
QoS Settings
LINSTOR implements QoS for managed resources by using sysfs properties that correspond to kernel variables related to block I/O operations. These sysfs properties can be limits on either bandwidth (bytes per second), or IOPS, or both.
The sysfs files and their corresponding LINSTOR properties are as follows:
sysfs (/sys/fs/ ) |
LINSTOR Property |
---|---|
|
|
|
|
|
|
|
|
Setting QoS Using LINSTOR sysfs Properties
These LINSTOR properties may be set using the set-property
command and may be set on the
following objects: volume, storage pool, resource, controller, or node. You can also set these
QoS properties on resource groups, volume groups, resource definitions, or volume definitions.
When you set a QoS property on a group or definition, resources created from the group or
definition will inherit the QoS settings.
Settings made to a group or definition will affect both existing and new resources created from the group or definition. |
The following example shows creating a resource group, then creating a volume group, then applying QoS settings to the volume group, and then spawning resources from the resource group. A verification command will show that the spawned resources inherit the QoS settings. The example uses an assumed previously created LINSTOR storage pool named pool1. You will need to replace this name with a storage pool name that exists in your environment.
# linstor resource-group create qos_limited --storage-pool pool1 --place-count 3 # linstor volume-group create qos_limited # linstor volume-group set-property qos_limited 0 sys/fs/blkio_throttle_write 1048576 # linstor resource-group spawn-resources qos_limited qos_limited_res 200M
To verify that the spawned resources inherited the QoS setting, you can show the contents of the corresponding sysfs file, on a node that contributes storage to the storage pool.
# cat /sys/fs/cgroup/blkio/blkio.throttle.write_bps_device 252:4 1048576
As the QoS properties are inherited and not copied, you will not see the property listed in any “child” objects that have been spawned from the “parent” group or definition. |
QoS Settings for a LINSTOR Volume Having Multiple DRBD Devices
A single LINSTOR volume can be composed of multiple DRBD devices. For example, DRBD with
external metadata will have three backing devices: a data (storage) device, a metadata device,
and the composite DRBD device (volume) provided to LINSTOR. If the data and metadata devices
correspond to different backing disks, then if you set a sysfs property for such a LINSTOR
volume, only the local data (storage) backing device will receive the property value in the
corresponding /sys/fs/cgroup/blkio/
file. Neither the device backing DRBD’s metadata, nor
the composite backing device provided to LINSTOR would receive the value. However, when DRBD’s
data and its metadata share the same backing disk, QoS settings will affect the performance of
both data and metadata operations.
QoS Settings for NVMe
In case a LINSTOR resource definition has an nvme-target
as well as an nvme-initiator
resource, both data (storage) backing devices of each node will receive the sysfs property
value. In case of the target, the data backing device will be the volume of either LVM or ZFS,
whereas in case of the initiator, the data backing device will be the connected nvme-device
,
regardless of which other LINSTOR layers, such as LUKS, NVMe, DRBD, and others (see
Using LINSTOR Without DRBD), are above that.
3.24. Getting Help
3.24.1. From the Command Line
A quick way to list available commands on the command line is to type
linstor
.
Further information about subcommands (e.g., list-nodes) can be retrieved in two ways:
# linstor node list -h # linstor help node list
Using the ‘help’ subcommand is especially helpful when LINSTOR is executed
in interactive mode (linstor interactive
).
One of the most helpful features of LINSTOR is its rich tab-completion, which can be used to complete basically every object LINSTOR knows about (e.g., node names, IP addresses, resource names, …). In the following examples, we show some possible completions, and their results:
# linstor node create alpha 1<tab> # completes the IP address if hostname can be resolved # linstor resource create b<tab> c<tab> # linstor assign-resource backups charlie
If tab-completion does not work out of the box, please try to source the appropriate file:
# source /etc/bash_completion.d/linstor # or # source /usr/share/bash_completion/completions/linstor
For zsh shell users, the linstor-client
command can generate a zsh compilation file,
that has basic support for command and argument completion.
# linstor gen-zsh-completer > /usr/share/zsh/functions/Completion/Linux/_linstor
3.24.2. SOS-Report
If something goes wrong and you need help finding the cause of the issue, you can use
# linstor sos-report create
The command above will create a new sos-report in /var/log/linstor/controller/
on the
controller node. Alternatively you can use
# linstor sos-report download
which will create a new sos-report and additionally downloads that report to the local machine into your current working directory.
This sos-report contains logs and useful debug-information from several sources
(Linstor-logs, dmesg
, versions of external tools used by LINSTOR, ip a
, database dump
and many more).
These information are stored for each node in plain text in the resulting .tar.gz
file.
3.24.3. From the Community
For help from the community please subscribe to our mailing list located here: https://lists.linbit.com/listinfo/drbd-user
3.24.4. GitHub
To file bug or feature request please check out our GitHub page https://github.com/linbit
3.24.5. Paid Support and Development
Alternatively, if you need to purchase remote installation services, 24/7 support, access to certified repositories, or feature development, please contact us: +1-877-454-6248 (1-877-4LINBIT) , International: +43-1-8178292-0 | [email protected]
Administering LINSTOR by GUI
4. LINBIT SDS GUI
LINBIT SDS GUI is a LINSTOR client alternative, currently in Technology Preview phase. This component is proprietary and users need to have access to LINBIT customer-only repositories to be able to use it.
4.1. Prerequisites
-
Access to LINBIT’s customer repositories.
-
Running and working LINSTOR controller instance.
4.2. Installing the LINBIT SDS GUI
Install LINSTOR GUI package on the same node as the LINSTOR controller and restart the linstor-controller
service.
On yum/dnf
based distributions you can install the software by entering the command:
yum install linstor-gui
On apt
based distributions you install the software by entering the command:
apt install linstor-gui
On Kubernetes, LINBIT SDS GUI is a built-in feature since linstor-controller v1.15.0.
4.3. Administering the LINSTOR Cluster by Using the LINBIT SDS GUI
You can access the LINBIT SDS GUI by opening an HTTP connection with the active LINSTOR
controller node via TCP port 3370. For example, if your LINSTOR controller’s IP address is
192.168.222.250, you would enter http://192.168.222.250:3370
into your web browser’s address
bar to use the LINBIT SDS GUI.
LINSTOR Integrations
5. LINSTOR Volumes in Kubernetes
This chapter describes the usage of LINSTOR® in Kubernetes (K8s) as managed by the operator and with volumes provisioned using the LINSTOR CSI plugin.
This chapter goes into great detail regarding all the install time options and various configurations possible with LINSTOR and Kubernetes. The chapter begins with some explanatory remarks and then moves onto deployment instructions. After that, there are instructions for getting started with LINSTOR to configure storage within a Kubernetes deployment. Following that, more advanced topics and configurations, such as snapshots and monitoring, are covered.
5.1. Kubernetes Introduction
Kubernetes is a container orchestrator. Kubernetes defines the behavior of
containers and related services, using declarative specifications. In this guide,
we will focus on using kubectl
to manipulate YAML files that define the
specifications of Kubernetes objects.
5.2. Deploying LINSTOR on Kubernetes
LINBIT® provides a LINSTOR Operator to commercial support customers. The Operator eases deployment of LINSTOR on Kubernetes by installing DRBD®, managing satellite and controller pods, and other related functions.
LINBIT’s container image repository (https://drbd.io), used by LINSTOR Operator, is only available to LINBIT customers or through LINBIT customer trial accounts. Contact LINBIT for information on pricing or to begin a trial. Alternatively, you can use the LINSTOR SDS upstream project named Piraeus, without being a LINBIT customer. |
LINSTOR Operator v2 is the recommended way of deploying LINBIT SDS for Kubernetes on new clusters. Users of existing Operator v1 deployments should continue to use their Helm deployments and skip to the, Operator v1 deployment instructions.
5.3. Deploying LINSTOR Operator v2
LINSTOR Operator v2 is deployed using
the Kustomize tool,
integrated with kubectl
.
5.3.1. Creating the Operator
To deploy the Operator, create a kustomization.yaml
file. This will declare your pull secret for drbd.io
and
allow you to pull in the Operator deployment. The Operator will be deployed in a new namespace linbit-sds
.
Make sure to replace MY_LINBIT_USER
and MY_LINBIT_PASSWORD
with your own credentials. You can find the latest
releases on charts.linstor.io.
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namespace: linbit-sds
resources:
- https://charts.linstor.io/static/v2.2.0.yaml (1)
generatorOptions:
disableNameSuffixHash: true
secretGenerator:
- name: drbdio-pull-secret
type: kubernetes.io/dockerconfigjson
literals:
- .dockerconfigjson={"auths":{"drbd.io":{"username":"MY_LINBIT_USER","password":"MY_LINBIT_PASSWORD"}}} (2)
1 | Replace with the latest release manifest from charts.linstor.io. |
2 | Replace MY_LINBIT_USER and MY_LINBIT_PASSWORD with your my.linbit.com credentials. |
Then, apply the kustomization.yaml
file, by using kubectl
command, and wait for the Operator to start:
$ kubectl apply -k . namespace/linbit-sds created ... $ kubectl -n linbit-sds wait pod --for=condition=Ready --all pod/linstor-operator-controller-manager-6d9847d857-zc985 condition met
The Operator is now ready to deploy LINBIT SDS for Kubernetes.
5.3.2. Deploying LINBIT SDS for Kubernetes
Deploying LINBIT SDS for Kubernetes with the Operator is as simple as creating a new LinstorCluster
resource and
waiting for the Operator to complete the setup:
$ kubectl create -f - <<EOF apiVersion: piraeus.io/v1 kind: LinstorCluster metadata: name: linstorcluster spec: {} EOF $ kubectl wait pod --for=condition=Ready -n linbit-sds --timeout=3m --all pod/ha-controller-4tgcg condition met pod/k8s-1-26-10.test condition met pod/linstor-controller-76459dc6b6-tst8p condition met pod/linstor-csi-controller-75dfdc967d-dwdx6 condition met pod/linstor-csi-node-9gcwj condition met pod/linstor-operator-controller-manager-6d9847d857-zc985 condition met
5.3.3. Configuring Storage
By default, LINBIT SDS for Kubernetes does not configure any storage. To add storage, you can configure a
LinstorSatelliteConfiguration
, which the Operator uses to configure one or more satellites.
The following example creates a simple FILE_THIN
pool and it does not require any additional set up on the host:
$ kubectl apply -f - <<EOF apiVersion: piraeus.io/v1 kind: LinstorSatelliteConfiguration metadata: name: storage-pool spec: storagePools: - name: pool1 fileThinPool: directory: /var/lib/linbit-sds/pool1 EOF
Other types of storage pools can be configured as well. Refer to the examples upstream.
5.3.4. Securing Operator v2 Deployment
By configuring key and certificate based encryption, you can make communication between certain LINSTOR components, for example, between LINSTOR satellite nodes and a LINSTOR controller node, or between the LINSTOR client and the LINSTOR API, more secure.
Configuring TLS Between the LINSTOR Controller and Satellite
To secure traffic between the LINSTOR controller and satellite nodes, you can configure TLS, either by using cert-manager or OpenSSL to create TLS certificates to encrypt the traffic.
Provisioning Keys and Certificates By Using cert-manager
This method requires a working cert-manager deployment in your cluster. For an alternative way to provision keys and certificates, see the OpenSSL section below.
The LINSTOR controller and satellite only need to trust each other. For that reason, you should only have a certificate authority (CA) for those components. Apply the following YAML configuration to your deployment to create a new cert-manager Issuer resource:
---
apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
name: ca-bootstrapper
namespace: linbit-sds
spec:
selfSigned: { }
---
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: linstor-internal-ca
namespace: linbit-sds
spec:
commonName: linstor-internal-ca
secretName: linstor-internal-ca
duration: 87600h # 10 years
isCA: true
usages:
- signing
- key encipherment
- cert sign
issuerRef:
name: ca-bootstrapper
kind: Issuer
---
apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
name: linstor-internal-ca
namespace: linbit-sds
spec:
ca:
secretName: linstor-internal-ca
Next, configure the new issuer resource to let the LINSTOR Operator provision the certificates needed to encrypt the controller and satellite traffic, by applying the following YAML configuration:
---
apiVersion: piraeus.io/v1
kind: LinstorCluster
metadata:
name: linstorcluster
spec:
internalTLS:
certManager:
name: linstor-internal-ca
kind: Issuer
---
apiVersion: piraeus.io/v1
kind: LinstorSatelliteConfiguration
metadata:
name: internal-tls
spec:
internalTLS:
certManager:
name: linstor-internal-ca
kind: Issuer
After applying the configurations above to your deployment, you can verify that TLS traffic encryption is working.
Provisioning Keys and Certificates By Using OpenSSL
If you completed the Provisioning Keys and Certificates By Using cert-manager section above, you can skip this section and go to the Verifying TLS Configuration section.
This method requires the openssl
program on the command line.
First, create a new CA by using a new key and a self-signed certificate. You can change options such as the encryption algorithm and expiry time to suit the requirements of your deployment.
# openssl req -new -newkey rsa:4096 -days 3650 -nodes -x509 \ -subj "/CN=linstor-internal-ca" \ -keyout ca.key -out ca.crt
Next, create two new keys, one for the LINSTOR controller, one for all satellites:
# openssl genrsa -out controller.key 4096 # openssl genrsa -out satellite.key 4096
Next, create a certificate for each key, valid for 10 years, signed by the CA that you created earlier:
# openssl req -new -sha256 -key controller.key -subj "/CN=linstor-controller" -out controller.csr # openssl req -new -sha256 -key satellite.key -subj "/CN=linstor-satellite" -out satellite.csr # openssl x509 -req -in controller.csr -CA ca.crt -CAkey ca.key \ -CAcreateserial -out controller.crt -days 3650 -sha256 # openssl x509 -req -in satellite.csr -CA ca.crt -CAkey ca.key \ -CAcreateserial -out satellite.crt -days 3650 -sha256
Next, create Kubernetes secrets from the created keys and certificates:
# kubectl create secret generic linstor-controller-internal-tls -n linbit-sds \ --type=kubernetes.io/tls --from-file=ca.crt=ca.crt --from-file=tls.crt=controller.crt \ --from-file=tls.key=controller.key # kubectl create secret generic linstor-satellite-internal-tls -n linbit-sds \ --type=kubernetes.io/tls --from-file=ca.crt=ca.crt --from-file=tls.crt=satellite.crt \ --from-file=tls.key=satellite.key
Finally, configure the Operator resources to reference the newly created secrets, by applying the following YAML configuration to your deployment:
---
apiVersion: piraeus.io/v1
kind: LinstorCluster
metadata:
name: linstorcluster
spec:
internalTLS:
secretName: linstor-controller-internal-tls
---
apiVersion: piraeus.io/v1
kind: LinstorSatelliteConfiguration
metadata:
name: internal-tls
spec:
internalTLS:
secretName: linstor-satellite-internal-tls
Verifying TLS Configuration
After configuring LINSTOR controller and satellite traffic encryption, you can next verify the secure TLS connection between the LINSTOR controller and a satellite by examining the output of a kubectl linstor node list
command. If TLS is enabled, the output will show (SSL)
next to an active satellite address.
# kubectl linstor node list +---------------------------------------------------------------------+ | Node | NodeType | Addresses | State | |=====================================================================| | node01.example.com | SATELLITE | 10.116.72.142:3367 (SSL) | Online | | node02.example.com | SATELLITE | 10.127.183.140:3367 (SSL) | Online | | node03.example.com | SATELLITE | 10.125.97.50:3367 (SSL) | Online | +---------------------------------------------------------------------+
The above command relies on the kubectl-linstor command to simplify entering LINSTOR client commands in Kubernetes. You can install the tool by following the instructions in Simplifying LINSTOR Client Command Entry.
|
If the output shows (PLAIN)
rather than (SSL)
, this indicates that the TLS configuration was not applied successfully. Check the status of the LinstorCluster
and LinstorSatellite
resources.
If the output shows (SSL)
, but the node remains offline, this usually indicates that a certificate is not trusted by the other party. Verify that the controller’s tls.crt
is trusted by the satellite’s ca.crt
and vice versa. The following shell function provides a quick way to verify that one TLS certificate is trusted by another:
function k8s_secret_trusted_by() { kubectl get secret -n linbit-sds \ -ogo-template='{{ index .data "tls.crt" | base64decode }}' \ "$1" > $1.tls.crt kubectl get secret -n linbit-sds \ -ogo-template='{{ index .data "ca.crt" | base64decode }}' \ "$2" > $2.ca.crt openssl verify -CAfile $2.ca.crt $1.tls.crt } # k8s_secret_trusted_by satellite-tls controller-tls
If TLS encryption was properly configured, output from running the above function should be:
satellite-tls.tls.crt: OK
The upstream Piraeus project’s reference documentation shows all available LinstorCluster
and LinstorSatelliteConfiguration
resources options related to TLS.
Configuring TLS for the LINSTOR API
This section describes how to set up TLS for the LINSTOR API. The API, served by the LINSTOR controller, is used by clients such as the CSI Driver and the Operator itself to control the LINSTOR cluster.
To follow the instructions in this section, you should be familiar with:
-
Editing
LinstorCluster
resources -
Using either cert-manager or OpenSSL to create TLS certificates
Provisioning Keys and Certificates By Using cert-manager
This method requires a working cert-manager deployment in your cluster. For an alternative way to provision keys and certificates, see the OpenSSL section below.
When using TLS, the LINSTOR API uses client certificates for authentication. It is good practice to have a separate CA just for these certificates. To do this, first apply the following YAML configuration to your deployment to create a certificate issuer.
--- apiVersion: cert-manager.io/v1 kind: Issuer metadata: name: ca-bootstrapper namespace: linbit-sds spec: selfSigned: { } --- apiVersion: cert-manager.io/v1 kind: Certificate metadata: name: linstor-api-ca namespace: linbit-sds spec: commonName: linstor-api-ca secretName: linstor-api-ca duration: 87600h # 10 years isCA: true usages: - signing - key encipherment - cert sign issuerRef: name: ca-bootstrapper kind: Issuer --- apiVersion: cert-manager.io/v1 kind: Issuer metadata: name: linstor-api-ca namespace: linbit-sds spec: ca: secretName: linstor-api-ca
Next, configure this issuer to let the Operator provision the needed certificates, by applying the following configuration.
--- apiVersion: piraeus.io/v1 kind: LinstorCluster metadata: name: linstorcluster spec: apiTLS: certManager: name: linstor-api-ca kind: Issuer
This completes the necessary steps for securing the LINSTOR API with TLS by using cert-manager. Skip to the Verifying LINSTOR API TLS Configuration section to verify that TLS is working.
Provisioning Keys and Certificates By Using OpenSSL
This method requires the openssl
program on the command line. For an alternative way to provision keys and certificates, see the cert-manager section above.
First, create a new certificate authority (CA) by using a new key and a self-signed certificate. You can change options such as the encryption algorithm and expiry time to suit the requirements of your deployment.
# openssl req -new -newkey rsa:4096 -days 3650 -nodes -x509 \ -subj "/CN=linstor-api-ca" \ -keyout ca.key -out ca.crt
Next, create two new keys, one for the LINSTOR API server, and one for all LINSTOR API clients:
# openssl genrsa -out api-server.key 4096 # openssl genrsa -out api-client.key 4096
Next, create a certificate for the server. Because the clients might use different shortened service names, you need to specify multiple subject names:
# cat /etc/ssl/openssl.cnf > api-csr.cnf # cat >> api-csr.cnf <<EOF [ v3_req ] subjectAltName = @alt_names [ alt_names ] DNS.0 = linstor-controller.linbit-sds.svc.cluster.local DNS.1 = linstor-controller.linbit-sds.svc DNS.2 = linstor-controller EOF # openssl req -new -sha256 -key api-server.key \ -subj "/CN=linstor-controller" -config api-csr.cnf \ -extensions v3_req -out api-server.csr # openssl x509 -req -in api-server.csr -CA ca.crt -CAkey ca.key \ -CAcreateserial -config api-csr.cnf \ -extensions v3_req -out api-server.crt \ -days 3650 -sha256
For the client certificate, setting one subject name is enough.
# openssl req -new -sha256 -key api-client.key \ -subj "/CN=linstor-client" -out api-client.csr # openssl x509 -req -in api-client.csr \ -CA ca.crt -CAkey ca.key -CAcreateserial \ -out api-client.crt \ -days 3650 -sha256
Next, create Kubernetes secrets from the created keys and certificates.
# kubectl create secret generic linstor-api-tls -n linbit-sds \ --type=kubernetes.io/tls --from-file=ca.crt=ca.crt --from-file=tls.crt=api-server.crt \ --from-file=tls.key=api-server.key # kubectl create secret generic linstor-client-tls -n linbit-sds \ --type=kubernetes.io/tls --from-file=ca.crt=ca.crt --from-file=tls.crt=api-client.crt \ --from-file=tls.key=api-client.key
Finally, configure the Operator resources to reference the newly created secrets. For simplicity, you can configure the same client secret for all components.
apiVersion: piraeus.io/v1 kind: LinstorCluster metadata: name: linstorcluster spec: apiTLS: apiSecretName: linstor-api-tls clientSecretName: linstor-client-tls csiControllerSecretName: linstor-client-tls csiNodeSecretName: linstor-client-tls
Verifying LINSTOR API TLS Configuration
You can verify that the API is running, secured by TLS, by manually connecting to the HTTPS endpoint using a curl
command.
# kubectl exec -n linbit-sds deploy/linstor-controller -- \ curl --key /etc/linstor/client/tls.key \ --cert /etc/linstor/client/tls.crt \ --cacert /etc/linstor/client/ca.crt \ https://linstor-controller.linbit-sds.svc:3371/v1/controller/version
If the command is successful, the API is using HTTPS, clients are able to connect to the controller with their certificates, and the command output should show something similar to this:
{"version":"1.20.2","git_hash":"58a983a5c2f49eb8d22c89b277272e6c4299457a","build_time":"2022-12-14T14:21:28+00:00","rest_api_version":"1.16.0"}%
If the command output shows an error, verify that the client certificates are trusted by the API secret, and vice versa. The following shell function provides a quick way to verify that one TLS certificate is trusted by another:
function k8s_secret_trusted_by() { kubectl get secret -n linbit-sds \ -ogo-template='{{ index .data "tls.crt" | base64decode }}' \ "$1" > $1.tls.crt kubectl get secret -n linbit-sds \ -ogo-template='{{ index .data "ca.crt" | base64decode }}' \ "$2" > $2.ca.crt openssl verify -CAfile $2.ca.crt $1.tls.crt } # k8s_secret_trusted_by satellite-tls controller-tls
If TLS encryption was properly configured, output from running the above function should be:
satellite-tls.tls.crt: OK
Another issue might be the API endpoint using a certificate that is not using the expected service name. A typical error message for this issue would be:
curl: (60) SSL: no alternative certificate subject name matches target host name 'linstor-controller.piraeus-datastore.svc'
In this case, make sure you have specified the right subject names when provisioning the certificates.
All available options are documented in the upstream Piraeus project’s reference documentation for LinstorCluster
.
Creating a Passphrase For LINSTOR
LINSTOR can use a passphrase for operations such as encrypting volumes and storing access credentials for backups.
To configure a LINSTOR passphrase in a Kubernetes deployment, the referenced secret must exist in the same namespace as the operator (by default linbit-sds
), and have a MASTER_PASSPHRASE
entry.
The following example YAML configuration for the .spec.linstorPassphraseSecret
configures a passphrase example-passphrase
.
Choose a different passphrase for your deployment. |
--- apiVersion: v1 kind: Secret metadata: name: linstor-passphrase namespace: linbit-sds data: # CHANGE THIS TO USE YOUR OWN PASSPHRASE! # Created by: echo -n "example-passphrase" | base64 MASTER_PASSPHRASE: ZXhhbXBsZS1wYXNzcGhyYXNl --- apiVersion: piraeus.io/v1 kind: LinstorCluster metadata: name: linstorcluster spec: linstorPassphraseSecret: linstor-passphrase
5.3.5. Using CustomResourceDefinitions in Operator v2 Deployments
Within LINSTOR Operator v2 deployments, you can change the cluster state by modifying LINSTOR related Kubernetes CustomResourceDefinitions
(CRDs) or check the status of a resource. An overview list of these resources follows. Refer to the upstream Piraeus project’s API reference (linked for each resource below) for more details.
LinstorCluster
-
This resource controls the state of the LINSTOR cluster and integration with Kubernetes.
LinstorSatelliteConfiguration
-
This resource controls the state of the LINSTOR satellites, optionally applying it to only a subset of nodes.
LinstorSatellite
-
This resource controls the state of a single LINSTOR satellite. This resource is not intended to be changed directly, rather it is created by the LINSTOR Operator by merging all matching
LinstorSatelliteConfiguration
resources. LinstorNodeConnection
-
This resource controls the state of the LINSTOR node connections.
5.3.6. Next Steps After Deploying LINSTOR Operator v2
After deploying LINBIT SDS for Kubernetes, you can continue with the Getting Started with LINBIT SDS Storage in Kubernetes, Configuring the DRBD Module Loader in Operator v2 Deployments, Using the Host Network for DRBD Replication in Operator v2 Deployments sections in this chapter, or refer to the available tutorials in the upstream Piraeus project.
5.4. Deploying LINSTOR Operator v1
If you plan to deploy LINSTOR Operator on a new cluster, you should use Operator v2. If you have already deployed the LINSTOR Operator v2, you can skip this section and proceed to other topics in the chapter, beginning with Deploying with an External LINSTOR Controller. |
The Operator v1 is installed using a Helm v3 chart as follows:
-
Create a Kubernetes secret containing your my.linbit.com credentials:
kubectl create secret docker-registry drbdiocred --docker-server=drbd.io \ --docker-username=<YOUR_LOGIN> --docker-email=<YOUR_EMAIL> --docker-password=<YOUR_PASSWORD>
The name of this secret must match the one specified in the Helm values, by default
drbdiocred
. -
Configure the LINSTOR database back end. By default, the chart configures etcd as database back end. The Operator can also configure LINSTOR to use Kubernetes as datastore directly. If you go the etcd route, you should configure persistent storage for it:
-
Use an existing storage provisioner with a default
StorageClass
. -
Disable persistence, for basic testing only. This can be done by adding
--set etcd.persistentVolume.enabled=false
to thehelm install
command below.
-
-
Read the storage guide and configure a basic storage setup for LINSTOR
-
Read the section on securing the deployment and configure as needed.
-
Select the appropriate kernel module injector using
--set
with thehelm install
command in the final step.-
Choose the injector according to the distribution you are using. Select the latest version from one of
drbd9-rhel7
,drbd9-rhel8
,… from http://drbd.io/ as appropriate. The drbd9-rhel8 image should also be used for RHCOS (OpenShift). For the SUSE CaaS Platform use the SLES injector that matches the base system of the CaaS Platform you are using (e.g.,drbd9-sles15sp1
). For example:operator.satelliteSet.kernelModuleInjectionImage=drbd.io/drbd9-rhel8:v9.1.8
-
Only inject modules that are already present on the host machine. If a module is not found, it will be skipped.
operator.satelliteSet.kernelModuleInjectionMode=DepsOnly
-
Disable kernel module injection if you are installing DRBD by other means. Deprecated by
DepsOnly
operator.satelliteSet.kernelModuleInjectionMode=None
-
-
Finally create a Helm deployment named
linstor-op
that will set up everything.helm repo add linstor https://charts.linstor.io helm install linstor-op linstor/linstor
Further deployment customization is discussed in the advanced deployment section
5.4.1. Kubernetes Back End for LINSTOR
The LINSTOR controller can use the Kubernetes API directly to persist its cluster state. To enable this back end, use the following override file during the chart installation:
etcd:
enabled: false
operator:
controller:
dbConnectionURL: k8s
It is NOT possible to migrate from an existing cluster with etcd back end to the Kubernetes back end. |
5.4.2. Creating Persistent Storage Volumes
You can use the pv-hostpath
Helm templates to create hostPath
persistent
volumes. Create as many PVs as needed to satisfy your configured etcd
replicas
(default 1).
Create the hostPath
persistent volumes, substituting cluster node
names accordingly in the nodes=
option:
helm repo add linstor https://charts.linstor.io helm install linstor-etcd linstor/pv-hostpath
By default, a PV is created on every control-plane
node. You can manually select the storage nodes by
passing --set "nodes={<NODE0>,<NODE1>,<NODE2>}"
to the install command.
The correct value to reference the node is the value of the kubernetes.io/hostname label. You can list the
value for all nodes by running kubectl get nodes -o custom-columns="Name:{.metadata.name},NodeName:{.metadata.labels['kubernetes\.io/hostname']}"
|
5.4.3. Using an Existing Database
LINSTOR can connect to an existing PostgreSQL, MariaDB or etcd database. For instance, for a PostgreSQL instance with the following configuration:
POSTGRES_DB: postgresdb POSTGRES_USER: postgresadmin POSTGRES_PASSWORD: admin123
The Helm chart can be configured to use this database rather than deploying an etcd cluster, by adding the following to the Helm install command:
--set etcd.enabled=false --set "operator.controller.dbConnectionURL=jdbc:postgresql://postgres/postgresdb?user=postgresadmin&password=admin123"
5.4.4. Configuring Storage With Operator v1
The LINSTOR Operator v1 can automate some basic storage set up for LINSTOR.
Configuring Storage Pool Creation
The LINSTOR Operator can be used to create LINSTOR storage pools. Creation is under control of the
LinstorSatelliteSet
resource:
$ kubectl get LinstorSatelliteSet.linstor.linbit.com linstor-op-ns -o yaml
kind: LinstorSatelliteSet
metadata:
[...]
spec:
[...]
storagePools:
lvmPools:
- name: lvm-thick
volumeGroup: drbdpool
lvmThinPools:
- name: lvm-thin
thinVolume: thinpool
volumeGroup: ""
zfsPools:
- name: my-linstor-zpool
zPool: for-linstor
thin: true
Creating Storage Pools at Installation Time
At installation time, by setting the value of operator.satelliteSet.storagePools
when running the helm install
command.
First create a file with the storage configuration such as:
operator:
satelliteSet:
storagePools:
lvmPools:
- name: lvm-thick
volumeGroup: drbdpool
This file can be passed to the Helm installation by entering the following command:
helm install -f <file> linstor-op linstor/linstor
Creating Storage Pools After Installation
On a cluster with the operator already configured (that is, after helm install
),
you can edit the LinstorSatelliteSet
configuration by entering the following command:
$ kubectl edit LinstorSatelliteSet.linstor.linbit.com <satellitesetname>
The storage pool configuration can be updated as in the example above.
Preparing Physical Devices
By default, LINSTOR expects the referenced VolumeGroups, ThinPools and so on to be present. You can use the
devicePaths: []
option to let LINSTOR automatically prepare devices for the pool. Eligible for automatic configuration
are block devices that:
-
Are a root device (no partition)
-
do not contain partition information
-
have more than 1 GiB
To enable automatic configuration of devices, set the devicePaths
key on storagePools
entries:
storagePools:
lvmPools:
- name: lvm-thick
volumeGroup: drbdpool
devicePaths:
- /dev/vdb
lvmThinPools:
- name: lvm-thin
thinVolume: thinpool
volumeGroup: linstor_thinpool
devicePaths:
- /dev/vdc
- /dev/vdd
Currently, this method supports creation of LVM and LVMTHIN storage pools.
Configuring LVM Storage Pools
The available keys for lvmPools
entries are:
-
name
name of the LINSTOR storage pool. [Required] -
volumeGroup
name of the VG to create. [Required] -
devicePaths
devices to configure for this pool. Must be empty and >= 1GiB to be recognized. [Optional] -
raidLevel
LVM raid level. [Optional] -
vdo
Enable [VDO] (requires VDO tools in the satellite). [Optional] -
vdoLogicalSizeKib
Size of the created VG (expected to be bigger than the backing devices by using VDO). [Optional] -
vdoSlabSizeKib
Slab size for VDO. [Optional]
Configuring LVM Thin Pools
-
name
name of the LINSTOR storage pool. [Required] -
volumeGroup
VG to use for the thin pool. If you want to usedevicePaths
, you must set this to""
. This is required because LINSTOR does not allow configuration of the VG name when preparing devices.thinVolume
name of the thin pool. [Required] -
devicePaths
devices to configure for this pool. Must be empty and >= 1GiB to be recognized. [Optional] -
raidLevel
LVM raid level. [Optional]
The volume group created by LINSTOR for LVM thin pools will always follow the scheme “linstor_$THINPOOL”. |
Configuring ZFS Storage Pools
-
name
name of the LINSTOR storage pool. [Required] -
zPool
name of thezpool
to use. Must already be present on all machines. [Required] -
thin
true
to use thin provisioning,false
otherwise. [Required]
Automatic Storage Type Provisioning (DEPRECATED)
ALL eligible devices will be prepared according to the value of operator.satelliteSet.automaticStorageType
, unless
they are already prepared using the storagePools
section. Devices are added to a storage pool based on the device
name (that is, all /dev/nvme1
devices will be part of the pool autopool-nvme1
)
The possible values for operator.satelliteSet.automaticStorageType
:
-
None
no automatic set up (default) -
LVM
create a LVM (thick) storage pool -
LVMTHIN
create a LVM thin storage pool -
ZFS
create a ZFS based storage pool (UNTESTED)
5.4.5. Securing Operator v1 Deployment
This section describes the different options for enabling security features available when using a LINSTOR Operator v1 deployment (using Helm) in Kubernetes.
Secure Communication with an Existing etcd Instance
Secure communication to an etcd
instance can be enabled by providing a CA certificate to the operator in form of a
Kubernetes secret. The secret has to contain the key ca.pem
with the PEM encoded CA certificate as value.
The secret can then be passed to the controller by passing the following argument to helm install
--set operator.controller.dbCertSecret=<secret name>
Authentication with etcd
Using Certificates
If you want to use TLS certificates to authenticate with an etcd
database, you need to set the following option on
Helm install:
--set operator.controller.dbUseClientCert=true
If this option is active, the secret specified in the above section must contain two additional keys:
-
client.cert
PEM formatted certificate presented toetcd
for authentication -
client.key
private key in PKCS8 format, matching the above client certificate.
Keys can be converted into PKCS8 format using openssl
:
openssl pkcs8 -topk8 -nocrypt -in client-key.pem -out client-key.pkcs8
5.4.6. Configuring Secure Communication Between LINSTOR Components in Operator v1 Deployments
The default communication between LINSTOR components is not secured by TLS. If this is needed for your setup, choose one of three methods:
Generating Keys and Certificates Using cert-manager
Requires cert-manager to be installed in your cluster.
Set the following options in your Helm override file:
linstorSslMethod: cert-manager
linstorHttpsMethod: cert-manager
Generate Keys and Certificates Using Helm
Set the following options in your Helm override file:
linstorSslMethod: helm
linstorHttpsMethod: helm
Generating Keys and Certificates Manually
Create a private key and self-signed certificate for your certificate authorities:
openssl req -new -newkey rsa:2048 -days 5000 -nodes -x509 -keyout ca.key \ -out ca.crt -subj "/CN=linstor-system" openssl req -new -newkey rsa:2048 -days 5000 -nodes -x509 -keyout client-ca.key \ -out client-ca.crt -subj "/CN=linstor-client-ca"
Create private keys, two for the controller, one for all nodes and one for all clients:
openssl genrsa -out linstor-control.key 2048 openssl genrsa -out linstor-satellite.key 2048 openssl genrsa -out linstor-client.key 2048 openssl genrsa -out linstor-api.key 2048
Create trusted certificates for controller and nodes:
openssl req -new -sha256 -key linstor-control.key -subj "/CN=system:control" \ -out linstor-control.csr openssl req -new -sha256 -key linstor-satellite.key -subj "/CN=system:node" \ -out linstor-satellite.csr openssl req -new -sha256 -key linstor-client.key -subj "/CN=linstor-client" \ -out linstor-client.csr openssl req -new -sha256 -key linstor-api.key -subj "/CN=linstor-controller" \ -out linstor-api.csr openssl x509 -req -in linstor-control.csr -CA ca.crt -CAkey ca.key -CAcreateserial \ -out linstor-control.crt -days 5000 -sha256 openssl x509 -req -in linstor-satellite.csr -CA ca.crt -CAkey ca.key -CAcreateserial \ -out linstor-satellite.crt -days 5000 -sha256 openssl x509 -req -in linstor-client.csr -CA client-ca.crt -CAkey client-ca.key \ -CAcreateserial -out linstor-client.crt -days 5000 -sha256 openssl x509 -req -in linstor-api.csr -CA client-ca.crt -CAkey client-ca.key \ -CAcreateserial -out linstor-api.crt -days 5000 -sha256 -extensions 'v3_req' \ -extfile <(printf '%s\n' '[v3_req]' extendedKeyUsage=serverAuth \ subjectAltName=DNS:linstor-op-cs.default.svc)
linstor-op-cs.default.svc in the last command needs to match create service name. With Helm, this is always
<release-name>-cs.<namespace>.svc .
|
Create Kubernetes secrets that can be passed to the controller and node pods:
kubectl create secret generic linstor-control --type=kubernetes.io/tls \ --from-file=ca.crt=ca.crt --from-file=tls.crt=linstor-control.crt \ --from-file=tls.key=linstor-control.key kubectl create secret generic linstor-satellite --type=kubernetes.io/tls \ --from-file=ca.crt=ca.crt --from-file=tls.crt=linstor-satellite.crt \ --from-file=tls.key=linstor-satellite.key kubectl create secret generic linstor-api --type=kubernetes.io/tls \ --from-file=ca.crt=client-ca.crt --from-file=tls.crt=linstor-api.crt \ --from-file=tls.key=linstor-api.key kubectl create secret generic linstor-client --type=kubernetes.io/tls \ --from-file=ca.crt=client-ca.crt --from-file=tls.crt=linstor-client.crt \ --from-file=tls.key=linstor-client.key
Pass the names of the created secrets to helm install
:
linstorHttpsControllerSecret: linstor-api
linstorHttpsClientSecret: linstor-client
operator:
controller:
sslSecret: linstor-control
satelliteSet:
sslSecret: linstor-satellite
Automatically Set the Passphrase for LINSTOR
LINSTOR needs to store confidential data to support encrypted information. This data is protected by a master passphrase. A passphrase is automatically generated on the first chart install.
If you want to use a custom passphrase, store it in a secret:
kubectl create secret generic linstor-pass --from-literal=MASTER_PASSPHRASE=<password>
On install, add the following arguments to the Helm command:
--set operator.controller.luksSecret=linstor-pass
5.4.7. Helm Installation Examples for Operator v1
All the below examples use the following sp-values.yaml
file. Feel
free to adjust this for your uses and environment. See [Configuring storage pool creation]
for further details.
operator: satelliteSet: storagePools: lvmThinPools: - name: lvm-thin thinVolume: thinpool volumeGroup: "" devicePaths: - /dev/sdb
Default install. This does not setup any persistence for the backing etcd key-value store. |
This is not suggested for any use outside of testing. |
kubectl create secret docker-registry drbdiocred --docker-server=drbd.io \ --docker-username=<YOUR_LOGIN> --docker-password=<YOUR_PASSWORD> helm repo add linstor https://charts.linstor.io helm install linstor-op linstor/linstor
LINBIT’s container image repository (http://drbd.io), used in the previous and
upcoming kubectl create commands, is only available to LINBIT customers or through LINBIT
customer trial accounts. Contact LINBIT for information on
pricing or to begin a trial. Alternatively, you can use the LINSTOR SDS upstream project named
Piraeus, without being a LINBIT
customer.
|
Install with LINSTOR storage-pools defined at install through
sp-values.yaml
, persistent hostPath
volumes, three etcd replicas, and by
compiling the DRBD kernel modules for the host kernels.
This should be adequate for most basic deployments. Note that
this deployment is not using the pre-compiled DRBD kernel modules just
to make this command more portable. Using the pre-compiled binaries
will make for a much faster install and deployment. Using the
Compile
option would not be suggested for use in a large Kubernetes clusters.
kubectl create secret docker-registry drbdiocred --docker-server=drbd.io \ --docker-username=<YOUR_LOGIN> --docker-password=<YOUR_PASSWORD> helm repo add linstor https://charts.linstor.io helm install linstor-etcd linstor/pv-hostpath --set "nodes={<NODE0>,<NODE1>,<NODE2>}" helm install -f sp-values.yaml linstor-op linstor/linstor --set etcd.replicas=3 \ --set operator.satelliteSet.kernelModuleInjectionMode=Compile
Install with LINSTOR storage-pools defined at install through
sp-values.yaml
, use an already created PostgreSQL DB (preferably
clustered), rather than etcd, and use already compiled kernel modules for
DRBD.
The PostgreSQL database in this particular example is reachable through a
service endpoint named postgres
. PostgreSQL itself is configured with
POSTGRES_DB=postgresdb
, POSTGRES_USER=postgresadmin
, and
POSTGRES_PASSWORD=admin123
kubectl create secret docker-registry drbdiocred --docker-server=drbd.io \ --docker-username=<YOUR_LOGIN> --docker-email=<YOUR_EMAIL> --docker-password=<YOUR_PASSWORD> helm repo add linstor https://charts.linstor.io helm install -f sp-values.yaml linstor-op linstor/linstor --set etcd.enabled=false \ --set "operator.controller.dbConnectionURL=jdbc:postgresql://postgres/postgresdb?user=postgresadmin&password=admin123"
5.4.8. Terminating Helm Deployment
To protect the storage infrastructure of the cluster from accidentally deleting vital components, it is necessary to perform some manual steps before deleting a Helm deployment.
-
Delete all volume claims managed by LINSTOR components. You can use the following command to get a list of volume claims managed by LINSTOR. After checking that none of the listed volumes still hold needed data, you can delete them using the generated
kubectl delete
command.$ kubectl get pvc --all-namespaces -o=jsonpath='{range .items[?(@.metadata.annotations.volume\.beta\.kubernetes\.io/storage-provisioner=="linstor.csi.linbit.com")]}kubectl delete pvc --namespace {.metadata.namespace} {.metadata.name}{"\n"}{end}' kubectl delete pvc --namespace default data-mysql-0 kubectl delete pvc --namespace default data-mysql-1 kubectl delete pvc --namespace default data-mysql-2
These volumes, once deleted, cannot be recovered. -
Delete the LINSTOR controller and satellite resources.
Deployment of LINSTOR satellite and controller is controlled by the
LinstorSatelliteSet
andLinstorController
resources. You can delete the resources associated with your deployment by usingkubectl
kubectl delete linstorcontroller <helm-deploy-name>-cs kubectl delete linstorsatelliteset <helm-deploy-name>-ns
After a short wait, the controller and satellite pods should terminate. If they continue to run, you can check the above resources for errors (they are only removed after all associated pods have terminated).
-
Delete the Helm deployment.
If you removed all PVCs and all LINSTOR pods have terminated, you can uninstall the Helm deployment
helm uninstall linstor-op
Due to the Helm’s current policy, the Custom Resource Definitions named LinstorController
andLinstorSatelliteSet
will not be deleted by the command. More information regarding Helm’s current position on CRDs can be found here.
5.4.9. Advanced Deployment Options for Operator v1
The Helm charts provide a set of further customization options for advanced use cases.
LINBIT’s container image repository (http://drbd.io), used in the Helm chart below, is only available to LINBIT customers or through LINBIT customer trial accounts. Contact LINBIT for information on pricing or to begin a trial. Alternatively, you can use the LINSTOR SDS upstream project named Piraeus, without being a LINBIT customer. |
global:
imagePullPolicy: IfNotPresent # empty pull policy means k8s default is used ("always" if tag == ":latest", "ifnotpresent" else) (1)
setSecurityContext: true # Force non-privileged containers to run as non-root users
# Dependency charts
etcd:
enabled: true
persistentVolume:
enabled: true
storage: 1Gi
replicas: 1 # How many instances of etcd will be added to the initial cluster. (2)
resources: {} # resource requirements for etcd containers (3)
image:
repository: gcr.io/etcd-development/etcd
tag: v3.4.15
stork:
enabled: false
storkImage: docker.io/openstorage/stork:2.8.2
schedulerImage: registry.k8s.io/kube-scheduler
schedulerTag: ""
replicas: 1 (2)
storkResources: {} # resources requirements for the stork plugin containers (3)
schedulerResources: {} # resource requirements for the kube-scheduler containers (3)
podsecuritycontext: {}
csi:
enabled: true
pluginImage: "drbd.io/linstor-csi:v1.1.0"
csiAttacherImage: registry.k8s.io/sig-storage/csi-attacher:v4.3.0
csiLivenessProbeImage: registry.k8s.io/sig-storage/livenessprobe:v2.10.0
csiNodeDriverRegistrarImage: registry.k8s.io/sig-storage/csi-node-driver-registrar:v2.8.0
csiProvisionerImage: registry.k8s.io/sig-storage/csi-provisioner:v3.5.0
csiSnapshotterImage: registry.k8s.io/sig-storage/csi-snapshotter:v6.2.1
csiResizerImage: registry.k8s.io/sig-storage/csi-resizer:v1.8.0
csiAttacherWorkerThreads: 10 (9)
csiProvisionerWorkerThreads: 10 (9)
csiSnapshotterWorkerThreads: 10 (9)
csiResizerWorkerThreads: 10 (9)
controllerReplicas: 1 (2)
nodeAffinity: {} (4)
nodeTolerations: [] (4)
controllerAffinity: {} (4)
controllerTolerations: [] (4)
enableTopology: true
resources: {} (3)
customLabels: {}
customAnnotations: {}
kubeletPath: /var/lib/kubelet (7)
controllerSidecars: []
controllerExtraVolumes: []
nodeSidecars: []
nodeExtraVolumes: []
priorityClassName: ""
drbdRepoCred: drbdiocred
linstorSslMethod: "manual" # <- If set to 'helm' or 'cert-manager' the certificates will be generated automatically
linstorHttpsMethod: "manual" # <- If set to 'helm' or 'cert-manager' the certificates will be generated automatically
linstorHttpsControllerSecret: "" # <- name of secret containing linstor server certificates+key. See docs/security.md
linstorHttpsClientSecret: "" # <- name of secret containing linstor client certificates+key. See docs/security.md
controllerEndpoint: "" # <- override to the generated controller endpoint. use if controller is not deployed via operator
psp:
privilegedRole: ""
unprivilegedRole: ""
operator:
replicas: 1 # <- number of replicas for the operator deployment (2)
image: "drbd.io/linstor-operator:v1.10.4"
affinity: {} (4)
tolerations: [] (4)
resources: {} (3)
customLabels: {}
customAnnotations: {}
podsecuritycontext: {}
args:
createBackups: true
createMonitoring: true
sidecars: []
extraVolumes: []
controller:
enabled: true
controllerImage: "drbd.io/linstor-controller:v1.23.0"
dbConnectionURL: ""
luksSecret: ""
dbCertSecret: ""
dbUseClientCert: false
sslSecret: ""
affinity: {} (4)
httpBindAddress: ""
httpsBindAddress: ""
tolerations: (4)
- key: node-role.kubernetes.io/master
operator: Exists
effect: NoSchedule
- key: node-role.kubernetes.io/control-plane
operator: Exists
effect: NoSchedule
resources: {} (3)
replicas: 1 (2)
additionalEnv: [] (5)
additionalProperties: {} (6)
sidecars: []
extraVolumes: []
customLabels: {}
customAnnotations: {}
satelliteSet:
enabled: true
satelliteImage: "drbd.io/linstor-satellite:v1.23.0"
storagePools: {}
sslSecret: ""
automaticStorageType: None
affinity: {} (4)
tolerations: [] (4)
resources: {} (3)
monitoringImage: "drbd.io/drbd-reactor:v1.2.0"
monitoringBindAddress: ""
kernelModuleInjectionImage: "drbd.io/drbd9-rhel7:v9.1.14"
kernelModuleInjectionMode: ShippedModules
kernelModuleInjectionAdditionalSourceDirectory: "" (8)
kernelModuleInjectionResources: {} (3)
kernelModuleInjectionExtraVolumeMounts: []
mountDrbdResourceDirectoriesFromHost: "" (10)
additionalEnv: [] (5)
sidecars: []
extraVolumes: []
customLabels: {}
customAnnotations: {}
haController:
enabled: false
image: drbd.io/linstor-k8s-ha-controller:v0.3.0
affinity: {} (4)
tolerations: [] (4)
resources: {} (3)
replicas: 1 (2)
customLabels: {}
customAnnotations: {}
1 | Sets the pull policy for all images. |
2 | Controls the number of replicas for each component. |
3 | Set container resource requests and limits. See the Kubernetes docs.
Most containers need a minimal amount of resources, except for:
|
4 | Affinity and toleration determine where pods are scheduled on the cluster. See the
Kubernetes docs on affinity and
toleration. This might be especially important for the operator.satelliteSet and csi.node*
values. To schedule a pod using a LINSTOR persistent volume, the node requires a running
LINSTOR satellite and LINSTOR CSI pod. |
5 | Sets additional environments variables to pass to the LINSTOR controller and satellites.
Uses the same format as the
env value of a container |
6 | Sets additional properties on the LINSTOR controller. Expects a simple mapping of <property-key>: <value> . |
7 | kubelet expects every CSI plugin to mount volumes under a specific subdirectory of its own state directory. By default, this state directory is /var/lib/kubelet . Some Kubernetes distributions use a different directory:
|
8 | Directory on the host that is required for building kernel modules. Only needed if using the Compile injection method. Defaults to /usr/src , which is where the actual kernel sources are stored on most distributions. Use "none" to not mount any additional directories. |
9 | Set the number of worker threads used by the CSI driver. Higher values put more load on the LINSTOR controller, which might lead to instability when creating many volumes at once. |
10 | If set to true, the satellite containers will have the following files and directories mounted from the host operating system:
|
5.4.10. High-Availability Deployment in Operator v1
To create a high-availability deployment of all components within a LINSTOR Operator v1 deployment, consult the upstream guide The default values are chosen so that scaling the components to multiple replicas ensures that the replicas are placed on different nodes. This ensures that a single node failures will not interrupt the service.
If you have deployed LINBIT SDS in Kubernetes by using the LINSTOR Operator v2, high availability is built into the deployment by default. |
Fast Workload Failover Using the High Availability Controller
When node failures occur, Kubernetes is very conservative in rescheduling stateful workloads. This means it can take more than 15 minutes for Pods to be moved from unreachable nodes. With the information available to DRBD and LINSTOR, this process can be sped up significantly.
The LINSTOR High Availability Controller (HA Controller) speeds up the failover process for stateful workloads using LINSTOR for storage. It monitors and manages any Pod that is attached to at least one DRBD resource.
For the HA Controller to work properly, you need quorum, that is at least three replicas (or two replicas + one diskless tiebreaker). If using lower replica counts, attached Pods will be ignored and are not eligible for faster failover.
The HA Controller is packaged as a Helm chart, and can be deployed using:
$ helm repo update $ helm install linstor-ha-controller linstor/linstor-ha-controller
If you are using the HA Controller in your cluster you can set additional parameters in all StorageClasses. These parameters ensure that the volume is not accidentally remounted as read-only, leading to degraded Pods.
parameters:
property.linstor.csi.linbit.com/DrbdOptions/auto-quorum: suspend-io
property.linstor.csi.linbit.com/DrbdOptions/Resource/on-no-data-accessible: suspend-io
property.linstor.csi.linbit.com/DrbdOptions/Resource/on-suspended-primary-outdated: force-secondary
property.linstor.csi.linbit.com/DrbdOptions/Net/rr-conflict: retry-connect
To exempt a Pod from management by the HA Controller, add the following annotation to the Pod:
$ kubectl annotate pod <podname> drbd.linbit.com/ignore-fail-over=""
5.4.11. Backing up the etcd Database
To create a backup of the etcd database (in LINSTOR Operator v1 deployments) and store it on your control host, enter the following commands:
kubectl exec linstor-op-etcd-0 -- etcdctl snapshot save /tmp/save.db
kubectl cp linstor-op-etcd-0:/tmp/save.db save.db
These commands will create a file save.db
on the machine you are running kubectl
from.
5.5. Deploying with an External LINSTOR Controller
The Operator can configure the satellites and CSI plugin to use an existing LINSTOR setup. This can be useful in cases where the storage infrastructure is separate from the Kubernetes cluster. Volumes can be provisioned in diskless mode on the Kubernetes nodes while the storage nodes will provide the backing disk storage.
5.5.1. Operator v2 Deployment with an External LINSTOR Controller
The instructions in this section describe how you can connect an Operator v2 LINBIT SDS deployment to an existing LINBIST SDS cluster that you manage outside Kubernetes.
To follow the steps in this section you should be familiar with editing LinstorCluster
resources.
Configuring the LinstorCluster
Resource
To use an externally managed LINSTOR cluster, specify the URL of the LINSTOR controller in the LinstorCluster
resource in a YAML configuration and apply it to your deployment. In the following example, the LINSTOR controller is reachable at http://linstor-controller.example.com:3370
.
apiVersion: piraeus.io/v1 kind: LinstorCluster metadata: name: linstorcluster spec: externalController: url: http://linstor-controller.example.com:3370
You can also specify an IP address rather than a hostname and domain for the controller. |
Configuring Host Networking for LINSTOR Satellites
Normally the pod network is not reachable from outside the Kubernetes cluster. In this case the external LINSTOR controller would not be able to communicate with the satellites in the Kubernetes cluster. For this reason, you need to configure your satellites to use host networking.
To use host networking, deploy a LinstorSatelliteConfiguration
resource by applying the following YAML configuration to your deployment:
apiVersion: piraeus.io/v1 kind: LinstorSatelliteConfiguration metadata: name: host-network spec: patches: - target: kind: Pod name: satellite patch: | apiVersion: v1 kind: Pod metadata: name: satellite spec: hostNetwork: true
Verifying an External LINSTOR Controller Configuration
You can verify that you have correctly configured your Kubernetes deployment to use an external LINSTOR controller by verifying the following:
-
The
Available
condition on theLinstorCluster
resource reports the expected URL for the external LINSTOR controller:$ kubectl get LinstorCluster -ojsonpath='{.items[].status.conditions[?(@.type=="Available")].message}{"\n"}' Controller 1.20.3 (API: 1.16.0, Git: 8d19a891df018f6e3d40538d809904f024bfe361) reachable at 'http://linstor-controller.example.com:3370'
-
The
linstor-csi-controller
deployment uses the expected URL:$ kubectl get -n linbit-sds deployment linstor-csi-controller -ojsonpath='{.spec.template.spec.containers[?(@.name=="linstor-csi")].env[?(@.name=="LS_CONTROLLERS")].value}{"\n"}' http://linstor-controller.example.com:3370
-
The
linstor-csi-node
deployment uses the expected URL:$ kubectl get -n linbit-sds daemonset linstor-csi-node -ojsonpath='{.spec.template.spec.containers[?(@.name=="linstor-csi")].env[?(@.name=="LS_CONTROLLERS")].value}{"\n"}' http://linstor-controller.example.com:3370
-
The Kubernetes nodes are registered as satellite nodes on the LINSTOR controller:
$ kubectl get nodes -owide NAME STATUS ROLES AGE VERSION INTERNAL-IP [...] k8s-1-26-10.test Ready control-plane 22m v1.26.3 192.168.122.10 [...] [...]
After getting the node names from the output of the above command, verify that the node names are also LINSTOR satellites by entering a LINSTOR
node list
command on your LINSTOR controller node.$ linstor node list ╭─────────────────────────────────────────────────────────────────────╮ ┊ Node ┊ NodeType ┊ Addresses ┊ State ┊ ╞═════════════════════════════════════════════════════════════════════╡ ┊ k8s-1-26-10.test ┊ SATELLITE ┊ 192.168.122.10:3366 (PLAIN) ┊ Online ┊ [...]
5.5.2. Operator v1 Deployment with an External LINSTOR Controller
To skip the creation of a LINSTOR controller deployment and configure the other components to use your existing LINSTOR
controller, use the following options when running helm install
:
-
operator.controller.enabled=false
This disables creation of theLinstorController
resource -
operator.etcd.enabled=false
Since no LINSTOR controller will run on Kubernetes, no database is required. -
controllerEndpoint=<url-of-linstor-controller>
The HTTP endpoint of the existing LINSTOR controller. For example:http://linstor.storage.cluster:3370/
After all pods are ready, you should see the Kubernetes cluster nodes as satellites in your LINSTOR setup.
Your Kubernetes nodes must be reachable using their IP by the controller and storage nodes. |
Create a storage class referencing an existing storage pool on your storage nodes.
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: linstor-on-k8s
provisioner: linstor.csi.linbit.com
parameters:
autoPlace: "3"
storagePool: existing-storage-pool
resourceGroup: linstor-on-k8s
You can provision new volumes by creating PVCs using your storage class. The volumes will first be placed only on nodes with the given storage pool, that is, your storage infrastructure. Once you want to use the volume in a pod, LINSTOR CSI will create a diskless resource on the Kubernetes node and attach over the network to the diskful resource.
5.6. Interacting with LINSTOR in Kubernetes
The controller pod includes a LINSTOR Client, making it easy to interact directly with LINSTOR. For instance:
kubectl exec deployment/linstor-op-cs-controller -- linstor storage-pool list
5.6.1. Simplifying LINSTOR Client Command Entry
To simplify entering LINSTOR client commands within a Kubernetes deployment, you can use the
kubectl-linstor
utility. This utility is available from the upstream Piraeus datastore
project. To download it, enter the following commands on your Kubernetes control plane node:
# KL_VERS=0.2.1 (1) # KL_ARCH=linux-amd64 (2) # curl -L -O \ https://github.com/piraeusdatastore/kubectl-linstor/releases/download/v$KL_VERS/kubectl-linstor-v$KL_VERS-$KL_ARCH.tar.gz
1 | Set the shell variable KL_VERS to the latest release version of the kubectl-linstor
utility, as shown on the
kubectl-linstor releases page. |
2 | Set the shell variable KL_ARCH to the architecture appropriate to your deployment and
supported by the utility’s available releases. |
If your deployment uses the LINSTOR Operator v2, you must use version 0.2.0 or higher
of the kubectl-linstor utility.
|
To install the utility, first extract it and then move the extracted executable file to a
directory in your $PATH
, for example, /usr/bin
. Then you can use kubectl-linstor
to get
access to the complete LINSTOR CLI.
$ kubectl linstor node list ╭────────────────────────────────────────────────────────────────────────────────────╮ ┊ Node ┊ NodeType ┊ Addresses ┊ State ┊ ╞════════════════════════════════════════════════════════════════════════════════════╡ ┊ kube-node-01.test ┊ SATELLITE ┊ 10.43.224.26:3366 (PLAIN) ┊ Online ┊ ┊ kube-node-02.test ┊ SATELLITE ┊ 10.43.224.27:3366 (PLAIN) ┊ Online ┊ ┊ kube-node-03.test ┊ SATELLITE ┊ 10.43.224.28:3366 (PLAIN) ┊ Online ┊ ┊ linstor-op-cs-controller-[...] ┊ CONTROLLER ┊ 172.24.116.114:3366 (PLAIN) ┊ Online ┊ ╰────────────────────────────────────────────────────────────────────────────────────╯
It also expands references to PVCs to the matching LINSTOR resource.
$ kubectl linstor resource list -r pvc:my-namespace/demo-pvc-1 --all pvc:my-namespace/demo-pvc-1 -> pvc-2f982fb4-bc05-4ee5-b15b-688b696c8526 ╭─────────────────────────────────────────────────────────────────────────────────────────────╮ ┊ ResourceName ┊ Node ┊ Port ┊ Usage ┊ Conns ┊ State ┊ CreatedOn ┊ ╞═════════════════════════════════════════════════════════════════════════════════════════════╡ ┊ pvc-[...] ┊ kube-node-01.test ┊ 7000 ┊ Unused ┊ Ok ┊ UpToDate ┊ 2021-02-05 09:16:09 ┊ ┊ pvc-[...] ┊ kube-node-02.test ┊ 7000 ┊ Unused ┊ Ok ┊ TieBreaker ┊ 2021-02-05 09:16:08 ┊ ┊ pvc-[...] ┊ kube-node-03.test ┊ 7000 ┊ InUse ┊ Ok ┊ UpToDate ┊ 2021-02-05 09:16:09 ┊ ╰─────────────────────────────────────────────────────────────────────────────────────────────╯
It also expands references of the form pod:[<namespace>/]<podname>
into a list resources in use by the pod.
This should only be necessary for investigating problems and accessing advanced functionality. Regular operation such as creating volumes should be achieved through the Kubernetes integration.
5.7. Getting Started with LINBIT SDS Storage in Kubernetes
Once all linstor-csi Pods are up and running, you can provision volumes using the usual Kubernetes workflows.
Configuring the behavior and properties of LINSTOR volumes deployed through Kubernetes is accomplished using Kubernetes StorageClass objects.
The resourceGroup parameter is mandatory. Usually you want it to be unique and the same as the storage class name.
|
Here below is the simplest practical StorageClass that can be used to deploy volumes:
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
# The name used to identify this StorageClass.
name: linstor-basic-storage-class
# The name used to match this StorageClass with a provisioner.
# linstor.csi.linbit.com is the name that the LINSTOR CSI plugin uses to identify itself
provisioner: linstor.csi.linbit.com
volumeBindingMode: WaitForFirstConsumer
parameters:
# LINSTOR will provision volumes from the drbdpool storage pool configured
# On the satellite nodes in the LINSTOR cluster specified in the plugin's deployment
storagePool: "lvm-thin"
resourceGroup: "linstor-basic-storage-class"
# Setting a fstype is required for "fsGroup" permissions to work correctly.
# Currently supported: xfs/ext4
csi.storage.k8s.io/fstype: xfs
The storagePool value, lvm-thin in the example YAML configuration file above, must match an available LINSTOR StoragePool. You can list storage pool information using the linstor storage-pool list command, executed within the running linstor-op-cs-controller pod, or by using the kubectl linstor storage-pool list command if you have installed the kubectl-linstor utility.
|
You can create the storage class with the following command:
kubectl create -f linstor-basic-sc.yaml
Now that your storage class is created, you can now create a persistent volume claim (PVC) which can be used to provision volumes known both to Kubernetes and LINSTOR:
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: my-first-linstor-volume
spec:
storageClassName: linstor-basic-storage-class
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 500Mi
You can create the PersistentVolumeClaim with the following command:
kubectl create -f my-first-linstor-volume-pvc.yaml
This will create a PersistentVolumeClaim, but no volume will be created just yet.
The storage class we used specified volumeBindingMode: WaitForFirstConsumer
, which
means that the volume is only created once a workload starts using it. This ensures
that the volume is placed on the same node as the workload.
For our example, we create a simple Pod, which mounts or volume by referencing the PersistentVolumeClaim. .my-first-linstor-volume-pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: fedora
namespace: default
spec:
containers:
- name: fedora
image: fedora
command: [/bin/bash]
args: ["-c", "while true; do sleep 10; done"]
volumeMounts:
- name: my-first-linstor-volume
mountPath: /data
ports:
- containerPort: 80
volumes:
- name: my-first-linstor-volume
persistentVolumeClaim:
claimName: "my-first-linstor-volume"
You can create the Pod with the following command:
kubectl create -f my-first-linstor-volume-pod.yaml
Running kubectl describe pod fedora
can be used to confirm that Pod
scheduling and volume attachment succeeded. Examining the PersistentVolumeClaim,
we can see that it is now bound to a volume.
To remove a volume, verify that no pod is using it and then delete the
PersistentVolumeClaim using the kubectl
command. For example, to remove the volume that we
just made, run the following two commands, noting that the Pod must be
unscheduled before the PersistentVolumeClaim will be removed:
kubectl delete pod fedora # unschedule the pod. kubectl get pod -w # wait for pod to be unscheduled kubectl delete pvc my-first-linstor-volume # remove the PersistentVolumeClaim, the PersistentVolume, and the LINSTOR Volume.
5.7.1. Available Parameters in a Storage Class
The following storage class contains all currently available parameters to configure the provisioned storage.
linstor.csi.linbit.com/ is an optional, but recommended prefix for LINSTOR CSI specific parameters.
|
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: full-example
provisioner: linstor.csi.linbit.com
parameters:
# CSI related parameters
csi.storage.k8s.io/fstype: xfs
# LINSTOR parameters
linstor.csi.linbit.com/autoPlace: "2"
linstor.csi.linbit.com/placementCount: "2"
linstor.csi.linbit.com/resourceGroup: "full-example"
linstor.csi.linbit.com/storagePool: "my-storage-pool"
linstor.csi.linbit.com/disklessStoragePool: "DfltDisklessStorPool"
linstor.csi.linbit.com/layerList: "drbd storage"
linstor.csi.linbit.com/placementPolicy: "AutoPlaceTopology"
linstor.csi.linbit.com/allowRemoteVolumeAccess: "true"
linstor.csi.linbit.com/encryption: "true"
linstor.csi.linbit.com/nodeList: "diskful-a diskful-b"
linstor.csi.linbit.com/clientList: "diskless-a diskless-b"
linstor.csi.linbit.com/replicasOnSame: "zone=a"
linstor.csi.linbit.com/replicasOnDifferent: "rack"
linstor.csi.linbit.com/disklessOnRemaining: "false"
linstor.csi.linbit.com/doNotPlaceWithRegex: "tainted.*"
linstor.csi.linbit.com/fsOpts: "-E nodiscard"
linstor.csi.linbit.com/mountOpts: "noatime"
linstor.csi.linbit.com/postMountXfsOpts: "extsize 2m"
# Linstor properties
property.linstor.csi.linbit.com/*: <x>
# DRBD parameters
DrbdOptions/*: <x>
5.7.2. csi.storage.k8s.io/fstype
The csi.storage.k8s.io/fstype
parameter sets the file system type to create for volumeMode: FileSystem
PVCs. Currently supported are:
-
ext4
(default) -
xfs
5.7.3. autoPlace
autoPlace
is an integer that determines the amount of replicas a volume of
this StorageClass will have. For instance, autoPlace: "3"
will produce
volumes with three-way replication. If neither autoPlace
nor nodeList
are
set, volumes will be automatically placed on one node.
If you use this option, you must not use nodeList .
|
You have to use quotes, otherwise Kubernetes will complain about a malformed StorageClass. |
This option (and all options which affect auto-placement behavior) modifies the number of LINSTOR nodes on which the underlying storage for volumes will be provisioned and is orthogonal to which kubelets those volumes will be accessible from. |
5.7.4. placementCount
placementCount
is an alias for autoPlace
5.7.5. resourceGroup
The LINSTOR Resource Group (RG) to associate with this StorageClass. If not set, a new RG will be created for each new PVC.
5.7.6. storagePool
storagePool
is the name of the LINSTOR storage pool that
will be used to provide storage to the newly-created volumes.
Only nodes configured with this same storage pool with be considered
for auto-placement. Likewise, for StorageClasses using
nodeList all nodes specified in that list must have this
storage pool configured on them.
|
5.7.7. disklessStoragePool
disklessStoragePool
is an optional parameter that only affects LINSTOR volumes
that are assigned as “diskless” to kubelets, that is, as clients. If you have a custom
diskless storage pool defined in LINSTOR, you will specify that here.
5.7.8. layerList
A comma-separated list of layers to use for the created volumes. The available layers and their order are described
towards the end of this section. Defaults to drbd,storage
5.7.9. placementPolicy
Select from one of the available volume schedulers:
-
AutoPlaceTopology
, the default: Use topology information from Kubernetes together with user provided constraints (seereplicasOnSame
andreplicasOnDifferent
). -
AutoPlace
Use the LINSTOR auto-placement feature, influenced byreplicasOnSame
andreplicasOnDifferent
-
FollowTopology
: Use CSI Topology information to place at least one volume in each “preferred” zone. Only usable if CSI Topology is enabled. -
Manual
: Use only the nodes listed innodeList
andclientList
. -
Balanced
: EXPERIMENTAL Place volumes across failure domains, using the least used storage pool on each selected node.
5.7.10. allowRemoteVolumeAccess
Control on which nodes a volume is accessible. The value for this option can take two different forms:
-
A simple
"true"
or"false"
allows access from all nodes, or only those nodes with diskful resources. -
Advanced rules, which allow more granular rules on which nodes can access the volume.
The current implementation can grant access to the volume for nodes that share the same labels. For example, if you want to allow access from all nodes in the same region and zone as a diskful resource, you could use:
parameters: linstor.csi.linbit.com/allowRemoteVolumeAccess: | - fromSame: - topology.kubernetes.io/region - topology.kubernetes.io/zone
You can specify multiple rules. The rules are additive, a node only need to match one rule to be assignable.
5.7.11. encryption
encryption
is an optional parameter that determines whether to encrypt
volumes. LINSTOR must be configured for encryption
for this to work properly.
5.7.12. nodeList
nodeList
is a list of nodes for volumes to be assigned to. This will assign
the volume to each node and it will be replicated among all of them. This
can also be used to select a single node by hostname, but it’s more flexible to use
replicasOnSame to select a single node.
If you use this option, you must not use autoPlace .
|
This option determines on which LINSTOR nodes the underlying storage for volumes will be provisioned and is orthogonal from which kubelets these volumes will be accessible. |
5.7.13. clientList
clientList
is a list of nodes for diskless volumes to be assigned to. Use in conjunction with nodeList
.
5.7.14. replicasOnSame
replicasOnSame
is a list of key
or key=value
items used as auto-placement selection
labels when autoPlace
is used to determine where to
provision storage. These labels correspond to LINSTOR node properties.
The operator periodically synchronizes all labels from Kubernetes Nodes, so you can use them as keys for scheduling constraints. |
Let’s explore this behavior with examples assuming a LINSTOR cluster such that node-a
is configured with the
following auxiliary property zone=z1
and role=backups
, while node-b
is configured with
only zone=z1
.
If we configure a StorageClass with autoPlace: "1"
and replicasOnSame: "zone=z1 role=backups"
,
then all volumes created from that StorageClass will be provisioned on node-a
,
since that is the only node with all of the correct key=value pairs in the LINSTOR
cluster. This is the most flexible way to select a single node for provisioning.
This guide assumes LINSTOR CSI version 0.10.0 or newer. All properties referenced in replicasOnSame
and replicasOnDifferent are interpreted as auxiliary properties. If you are using an older version of LINSTOR CSI, you
need to add the Aux/ prefix to all property names. So replicasOnSame: "zone=z1" would be replicasOnSame: "Aux/zone=z1"
Using Aux/ manually will continue to work on newer LINSTOR CSI versions.
|
If we configure a StorageClass with autoPlace: "1"
and replicasOnSame: "zone=z1"
,
then volumes will be provisioned on either node-a
or node-b
as they both have
the zone=z1
aux prop.
If we configure a StorageClass with autoPlace: "2"
and replicasOnSame: "zone=z1 role=backups"
,
then provisioning will fail, as there are not two or more nodes that have
the appropriate auxiliary properties.
If we configure a StorageClass with autoPlace: "2"
and replicasOnSame: "zone=z1"
,
then volumes will be provisioned on both node-a
and node-b
as they both have
the zone=z1
aux prop.
You can also use a property key without providing a value to ensure all replicas are placed on nodes with the same property value,
with caring about the particular value. Assuming there are 4 nodes, node-a1
and node-a2
are configured with zone=a
. node-b1
and node-b2
are configured with zone=b
. Using autoPlace: "2"
and replicasOnSame: "zone"
will place on either node-a1
and node-a2
OR on node-b1
and node-b2
.
5.7.15. replicasOnDifferent
replicasOnDifferent
takes a list of properties to consider, same as replicasOnSame.
There are two modes of using replicasOnDifferent
:
-
Preventing volume placement on specific nodes:
If a value is given for the property, the nodes which have that property-value pair assigned will be considered last.
Example:
replicasOnDifferent: "no-csi-volumes=true"
will place no volume on any node with propertyno-csi-volumes=true
unless there are not enough other nodes to fulfill theautoPlace
setting. -
Distribute volumes across nodes with different values for the same key:
If no property value is given, LINSTOR will place the volumes across nodes with different values for that property if possible.
Example: Assuming there are 4 nodes,
node-a1
andnode-a2
are configured withzone=a
.node-b1
andnode-b2
are configured withzone=b
. Using a StorageClass withautoPlace: "2"
andreplicasOnDifferent: "zone"
, LINSTOR will create one replica on eithernode-a1
ornode-a2
and one replica on eithernode-b1
ornode-b2
.
5.7.16. disklessOnRemaining
Create a diskless resource on all nodes that were not assigned a diskful resource.
5.7.17. doNotPlaceWithRegex
Do not place the resource on a node which has a resource with a name matching the regular expression.
5.7.18. fsOpts
fsOpts
is an optional parameter that passes options to the volume’s
file system at creation time.
These values are specific to your chosen file system. |
5.7.19. mountOpts
mountOpts
is an optional parameter that passes options to the volume’s
file system at mount time.
5.7.20. postMountXfsOpts
Extra arguments to pass to xfs_io
, which gets called before right before first use of the volume.
5.7.21. property.linstor.csi.linbit.com/*
Parameters starting with property.linstor.csi.linbit.com/
are translated to LINSTOR properties that are set on the
Resource Group associated with the StorageClass.
For example, to set DrbdOptions/auto-quorum
to disabled
, use:
property.linstor.csi.linbit.com/DrbdOptions/auto-quorum: disabled
The full list of options is available here
5.7.22. DrbdOptions/*: <x>
This option is deprecated, use the more general property.linstor.csi.linbit.com/* form.
|
Advanced DRBD options to pass to LINSTOR. For example, to change the replication protocol, use
DrbdOptions/Net/protocol: "A"
.
5.8. Snapshots
Snapshots create a copy of the volume content at a particular point in time. This copy remains untouched when you make modifications to the volume content. This, for example, enables you to create backups of your data before performing modifications or deletions on your data.
Because a backup is useless unless you have a way to restore it, this section describes how to create a snapshot, and how to restore it, for example, in the case of accidental deletion of your data.
The next subsection contains instructions around snapshots within Operator v2 deployments. If you have deployed LINBIT SDS in Kubernetes by using Operator v1, skip ahead to the [s-kubernetes-add-snaphot-support-v1] subsection.
5.8.1. Working With Snapshots
Before you can add snapshot support within a LINBIT SDS deployment, you need to meet the following environment prerequisites:
-
Your cluster has a storage pool supporting snapshots. LINSTOR supports snapshots for
LVM_THIN
,FILE_THIN
,ZFS
andZFS_THIN
pools. -
You have a
StorageClass
,PersistentVolumeClaim
, andDeployment
that uses a storage pool that supports snapshots. -
Your cluster has a CSI snapshotter (
snapshot-controller
) deployed. To verify if it is already deployed, you can enter the following command:$ kubectl api-resources --api-group=snapshot.storage.k8s.io -oname
Output should be similar to the following if a snapshot controller is already deployed:
volumesnapshotclasses.snapshot.storage.k8s.io volumesnapshotcontents.snapshot.storage.k8s.io volumesnapshots.snapshot.storage.k8s.io
If output from the command is empty, you can deploy a snapshot controller by entering the following commands:
$ kubectl apply -k https://github.com/kubernetes-csi/external-snapshotter//client/config/crd $ kubectl apply -k https://github.com/kubernetes-csi/external-snapshotter//deploy/kubernetes/snapshot-controller
Creating a Snapshot
To create a volume snapshot, you first need to create a volume snapshot class (VolumeSnapshotClass
). This volume snapshot class will specify the linstor.csi.linbit.com
provisioner, and sets the clean-up policy for the snapshots to Delete
. This means that deleting the Kubernetes resources will also delete the snapshots in LINSTOR.
You can create a volume snapshot class by entering the following command:
$ kubectl apply -f - <<EOF apiVersion: snapshot.storage.k8s.io/v1 kind: VolumeSnapshotClass metadata: name: linbit-sds-snapshots driver: linstor.csi.linbit.com deletionPolicy: Delete EOF
To create a snapshot, you create a VolumeSnapshot
resource. The VolumeSnapshot
resource needs to reference a snapshot-compatible PersistentVolumeClaim
resource, and the VolumeSnapshotClass
that you just created. For example, you could create a snapshot (named data-volume-snapshot-1
) of a PVC named data-volume
by entering the following command:
$ kubectl apply -f - <<EOF apiVersion: snapshot.storage.k8s.io/v1 kind: VolumeSnapshot metadata: name: data-volume-snapshot-1 spec: volumeSnapshotClassName: linbit-sds-snapshots source: persistentVolumeClaimName: data-volume EOF
Verifying Snapshot Creation
You can verify the creation of a snapshot by entering the following commands:
$ kubectl wait volumesnapshot --for=jsonpath='{.status.readyToUse}'=true data-volume-snapshot-1 volumesnapshot.snapshot.storage.k8s.io/data-volume-snapshot-1 condition met $ kubectl get volumesnapshot data-volume-snapshot-1
Output should show a table of information about the volume snapshot resource, similar to the following:
NAME READYTOUSE SOURCEPVC SOURCESNAPSHOTCONTENT RESTORESIZE SNAPSHOTCLASS data-volume-snapshot-1 true data-volume 1Gi linbit-sds-snapshots
You can further verify the snapshot in LINSTOR, by entering the following command:
$ kubectl -n linbit-sds exec deploy/linstor-controller -- linstor snapshot list
Output should show a table similar to the following:
+-----------------------------------------------------------------------------------------+ | ResourceName | SnapshotName | NodeNames | Volumes | CreatedOn | State | |=========================================================================================| | pvc-[...] | snapshot-[...] | kube-0 | 0: 1 GiB | 2023-02-13 15:36:18 | Successful | +-----------------------------------------------------------------------------------------+
Restoring a Snapshot
To restore a snapshot, you will need to create a new PVC to recover the volume snapshot to. You will replace the existing PVC, named data-volume
in this example, with a new version based on the snapshot.
First, stop the deployment that uses the data-volume
PVC. In this example, the deployment is named volume-logger
.
$ kubectl scale deploy/volume-logger --replicas=0 deployment.apps "volume-logger" deleted $ kubectl rollout status deploy/volume-logger deployment "volume-logger" successfully rolled out
Next, remove the PVC. You still have the snapshot resource, so this is a safe operation.
$ kubectl delete pvc/data-volume persistentvolumeclaim "data-volume" deleted
Next, create a new PVC by referencing a previously created snapshot. This will create a volume which uses the data from the referenced snapshot.
kubectl apply -f - <<EOF apiVersion: v1 kind: PersistentVolumeClaim metadata: name: data-volume spec: storageClassName: linbit-sds-storage resources: requests: storage: 1Gi dataSource: apiGroup: snapshot.storage.k8s.io kind: VolumeSnapshot name: data-volume-snapshot-1 accessModes: - ReadWriteOnce EOF
Because you named the new volume, data-volume
, the same as the previous volume, you can just scale up the Deployment
again, and the new pod will start using the restored volume.
$ kubectl scale deploy/volume-logger --replicas=1 deployment.apps/volume-logger scaled
5.8.2. Storing Snapshots on S3 Storage
LINSTOR can store snapshots on S3 compatible storage for disaster recovery. This is integrated in Kubernetes using a special VolumeSnapshotClass:
---
kind: VolumeSnapshotClass
apiVersion: snapshot.storage.k8s.io/v1
metadata:
name: linstor-csi-snapshot-class-s3
driver: linstor.csi.linbit.com
deletionPolicy: Retain
parameters:
snap.linstor.csi.linbit.com/type: S3
snap.linstor.csi.linbit.com/remote-name: backup-remote
snap.linstor.csi.linbit.com/allow-incremental: "false"
snap.linstor.csi.linbit.com/s3-bucket: snapshot-bucket
snap.linstor.csi.linbit.com/s3-endpoint: s3.us-west-1.amazonaws.com
snap.linstor.csi.linbit.com/s3-signing-region: us-west-1
snap.linstor.csi.linbit.com/s3-use-path-style: "false"
# Refer here to the secret that holds access and secret key for the S3 endpoint.
# See below for an example.
csi.storage.k8s.io/snapshotter-secret-name: linstor-csi-s3-access
csi.storage.k8s.io/snapshotter-secret-namespace: storage
---
kind: Secret
apiVersion: v1
metadata:
name: linstor-csi-s3-access
namespace: storage
immutable: true
type: linstor.csi.linbit.com/s3-credentials.v1
stringData:
access-key: access-key
secret-key: secret-key
Check the LINSTOR snapshot guide on the exact meaning of the
snap.linstor.csi.linbit.com/
parameters. The credentials used to log in are stored in a separate secret, as show in
the example above.
Referencing the above storage class when creating snapshots causes the snapshots to be automatically uploaded to the configured S3 storage.
Restoring From Remote Snapshots
Restoring from remote snapshots is an important step in disaster recovery. A snapshot needs to be registered with Kubernetes before it can be used to restore.
If the snapshot that should be restored is part of a backup to S3, the LINSTOR “remote” needs to be configured first.
linstor remote create s3 backup-remote s3.us-west-1.amazonaws.com \ snapshot-bucket us-west-1 access-key secret-key linstor backup list backup-remote
The snapshot you want to register needs to be one of the listed snapshots.
To register the snapshot with Kubernetes, you need to create two resources, one VolumeSnapshotContent referencing the ID of the snapshot and one VolumeSnapshot, referencing the content.
---
apiVersion: snapshot.storage.k8s.io/v1
kind: VolumeSnapshot
metadata:
name: example-backup-from-s3
namespace: project
spec:
source:
volumeSnapshotContentName: restored-snap-content-from-s3
volumeSnapshotClassName: linstor-csi-snapshot-class-s3
---
apiVersion: snapshot.storage.k8s.io/v1
kind: VolumeSnapshotContent
metadata:
name: restored-snap-content-from-s3
spec:
deletionPolicy: Delete
driver: linstor.csi.linbit.com
source:
snapshotHandle: snapshot-id
volumeSnapshotClassName: linstor-csi-snapshot-class-s3
volumeSnapshotRef:
apiVersion: snapshot.storage.k8s.io/v1
kind: VolumeSnapshot
name: example-backup-from-s3
namespace: project
Once applied, the VolumeSnapshot should be shown as ready
, at which point you can reference it as a dataSource
in a
PVC.
5.9. Volume Accessibility and Locality
LINSTOR volumes are typically accessible both locally and over the network. The CSI driver will ensure that the volume is accessible on whatever node was selected for the consumer. The driver also provides options to ensure volume locality (the consumer is placed on the same node as the backing data) and restrict accessibility (only a subset of nodes can access the volume over the network).
Volume locality is achieved by setting volumeBindingMode: WaitForFirstConsumer
in the storage class. This tell
Kubernetes and the CSI driver to wait until the first consumer (Pod) referencing the PVC is scheduled. The CSI driver
then provisions the volume with backing data on the same node as the consumer. In case a node without appropriate
storage pool was selected, a replacement node in the set of accessible nodes is chosen (see below).
Volume accessibility is controlled by the
allowRemoteVolumeAccess
parameter. Whenever the CSI plugin needs to
place a volume, this parameter is consulted to get the set of “accessible” nodes. This means they can share volumes
placed on them through the network. This information is also propagated to Kubernetes using label selectors on the PV.
5.9.1. Volume Accessibility and Locality Examples
The following example show common scenarios where you want to optimize volume accessibility and locality. It also includes examples of how to spread volume replicas across zones in a cluster.
Single-Zone Homogeneous Clusters
The cluster only spans a single zone, so latency between nodes is low. The cluster is homogeneous, that is, all nodes are configured similarly. All nodes have their own local storage pool.
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: linstor-storage
provisioner: linstor.csi.linbit.com
volumeBindingMode: WaitForFirstConsumer (1)
parameters:
linstor.csi.linbit.com/storagePool: linstor-pool (2)
linstor.csi.linbit.com/placementCount: "2" (3)
linstor.csi.linbit.com/allowRemoteVolumeAccess: "true" (4)
1 | Enable late volume binding. This places one replica on the same node as the first consuming pod, if possible. |
2 | Set the storage pool(s) to use. |
3 | Ensure that the data is replicated, so that at least 2 nodes store the data. |
4 | Allow using the volume even on nodes without replica. Since all nodes are connected equally, performance impact should be manageable. |
Multi-Zonal Homogeneous Clusters
As before, in our homogeneous cluster all nodes are configured similarly with their own local storage pool. The cluster spans now multiple zones, with increased latency across nodes in different zones. To ensure low latency, we want to restrict access to the volume with a local replica to only those zones that do have a replica. At the same time, we want to spread our data across multiple zones.
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: linstor-storage
provisioner: linstor.csi.linbit.com
volumeBindingMode: WaitForFirstConsumer (1)
parameters:
linstor.csi.linbit.com/storagePool: linstor-pool (2)
linstor.csi.linbit.com/placementCount: "2" (3)
linstor.csi.linbit.com/allowRemoteVolumeAccess: | (4)
- fromSame:
- topology.kubernetes.io/zone
linstor.csi.linbit.com/replicasOnDifferent: topology.kubernetes.io/zone (5)
1 | Enable late volume binding. This places one replica on the same node as the first consuming pod, if possible. |
2 | Set the storage pool(s) to use. |
3 | Ensure that the data is replicated, so that at least 2 nodes store the data. |
4 | Allow using the volume on nodes in the same zone as a replica, under the assumption that zone internal networking is fast and low latency. |
5 | Spread the replicas across different zones. |
Multi-Region Clusters
If your cluster spans multiple regions, you do not want to incur the latency penalty to replicate your data across regions. To accomplish this, you can configure your storage class to just replicate data in the same zone.
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: linstor-storage
provisioner: linstor.csi.linbit.com
volumeBindingMode: WaitForFirstConsumer (1)
parameters:
linstor.csi.linbit.com/storagePool: linstor-pool (2)
linstor.csi.linbit.com/placementCount: "2" (3)
linstor.csi.linbit.com/allowRemoteVolumeAccess: | (4)
- fromSame:
- topology.kubernetes.io/zone
linstor.csi.linbit.com/replicasOnSame: topology.kubernetes.io/region (5)
1 | Enable late volume binding. This places one replica on the same node as the first consuming pod, if possible. |
2 | Set the storage pool(s) to use. |
3 | Ensure that the data is replicated, so that at least 2 nodes store the data. |
4 | Allow using the volume on nodes in the same zone as a replica, under the assumption that zone internal networking is fast and low latency. |
5 | Restrict replicas to only a single region. |
Cluster with External Storage
Our cluster now only consists of compute nodes without local storage. Any volume access has to occur through remote volume access.
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: linstor-storage
provisioner: linstor.csi.linbit.com
parameters:
linstor.csi.linbit.com/storagePool: linstor-pool (1)
linstor.csi.linbit.com/placementCount: "1" (2)
linstor.csi.linbit.com/allowRemoteVolumeAccess: "true" (3)
1 | Set the storage pool(s) to use. |
2 | Assuming we only have one storage host, we can only place a single volume without additional replicas. |
3 | Our worker nodes need to be allowed to connect to the external storage host. |
5.10. LINSTOR Affinity Controller
Volume Accessibility is controlled by the node affinity of the PersistentVolume (PV). This affinity is static, that is once defined it cannot be changed.
This can be an issue if you want to use a strict affinity: Your PV is pinned to specific nodes, but you might want to remove or add nodes. While LINSTOR can move the volume (for example: this happens automatically if you remove a node in Kubernetes), the PV affinity is not updated to reflect this.
This is where the LINSTOR Affinity Controller comes in: it watches PVs and compares their affinity with the volumes’ states in LINSTOR. If they go out of sync, the PV is replaced with an updated version.
The LINSTOR Affinity Controller is packaged in a Helm chart. If you install it in the same namespace as the Operator, simply run:
$ helm repo update $ helm install linstor-affinity-controller linstor/linstor-affinity-controller
Additional options for the chart are available at the upstream project.
5.11. Volume Locality Optimization Using LINSTOR Scheduler
LINBIT maintains an open source plugin for the Kubernetes scheduler. The scheduler will take the current placement of volumes into account and optimize for data locality. If possible, the pod will be assigned to a node that also hosts replicas of attached volumes, reducing latency for read operations.
The scheduler is available as a separate chart from artifacthub.io. The chart will deploy a new scheduler, which you can later use when creating pod resources:
apiVersion: v1
kind: Pod
metadata:
name: busybox
spec:
schedulerName: linstor-scheduler (1)
containers:
- name: busybox
image: busybox
command: ["tail", "-f", "/dev/null"]
volumeMounts:
- name: my-first-linstor-volume
mountPath: /data
ports:
- containerPort: 80
volumes:
- name: my-first-linstor-volume
persistentVolumeClaim:
claimName: "test-volume"
1 | Add the name of the scheduler to your pod. |
5.12. Configuring the DRBD Module Loader in Operator v2 Deployments
To follow the steps in this section, you should be familiar with editing
LinstorSatelliteConfiguration
resources.
|
The DRBD module loader is the component responsible for making the DRBD kernel module available, in addition to loading other useful kernel modules for LINBIT SDS in Kubernetes. This section describes how you can configure various aspects of the DRBD kernel module loader, within a LINSTOR Operator v2 deployment.
Besides the DRBD kernel module, these modules are also loaded if available:
Module | Purpose |
---|---|
|
dependency for DRBD |
|
LINSTOR NVME layer |
|
LINSTOR when using loop devices as backing disks |
|
LINSTOR writecache layer |
|
LINSTOR cache layer |
|
LINSTOR thin-provisioned storage |
|
LINSTOR Snapshots |
|
LINSTOR encrypted volumes |
5.12.1. Disabling the DRBD Module Loader
In some circumstances it might be necessary to disable the DRBD module loader entirely. For example, if you are using an immutable operating system, and DRBD and other modules are loaded as part of the host configuration.
To disable the DRBD module loader completely, apply the following YAML configuration to your deployment:
apiVersion: piraeus.io/v1 kind: LinstorSatelliteConfiguration metadata: name: no-loader spec: patches: - target: kind: Pod name: satellite patch: | apiVersion: v1 kind: Pod metadata: name: satellite spec: initContainers: - name: drbd-module-loader $patch: delete
5.12.2. Selecting a Different DRBD Module Loader Version
By default, the Operator will try to find a DRBD module loader that matches the host operating system. The Operator determines the host distribution by inspecting the .status.nodeInfo.osImage
field of the Kubernetes Node
resource. A user-defined image can be used if the automatic mapping does not succeed or if you have different module loading requirements.
The following YAML configuration overrides the chosen DRBD module loader image with a user-defined image example.com/drbd-loader:v9
:
apiVersion: piraeus.io/v1 kind: LinstorSatelliteConfiguration metadata: name: custom-drbd-module-loader-image spec: patches: - target: kind: Pod name: satellite patch: | apiVersion: v1 kind: Pod metadata: name: satellite spec: initContainers: - name: drbd-module-loader image: example.com/drbd-loader:v9
drbd.io
, available to LINBIT customers only, maintains the following module loader container images:
Image | Distribution |
---|---|
|
Amazon Linux 2 |
|
Ubuntu 18.04 |
|
Ubuntu 20.04 |
|
Ubuntu 22.04 |
|
Red Hat Enterprise Linux 7 |
|
Red Hat Enterprise Linux 8 |
|
Red Hat Enterprise Linux 9 |
If you need to create a module loader image for your own distribution, you can refer to the container source files which are available in the upstream Piraeus project.
5.12.3. Changing How the Module Loader Loads the DRBD Kernel Module
By default, the DRBD module loader will try to build the kernel module from source. The module loader can also be configured to load the module from a DEB or RPM package included in the image, or skip loading DRBD entirely.
To change the behavior of the DRBD module loader, set the LB_HOW
environment variable to an appropriate value shown in the following table:
LB_HOW |
Module Loader Behavior |
---|---|
|
The default value. Builds the DRBD module from source and tries to load all optional modules from the host. |
|
Searches for |
|
Only tries to load the optional modules. No DRBD module will be loaded. |
After setting the LB_HOW
environment variable, apply the following YAML configuration to your deployment. Based on the name within the metadata section, the example below would be used with an LB_HOW
environment variable that was set to deps_only
.
apiVersion: piraeus.io/v1 kind: LinstorSatelliteConfiguration metadata: name: no-drbd-module-loader spec: patches: - target: kind: Pod name: satellite patch: | apiVersion: v1 kind: Pod metadata: name: satellite spec: initContainers: - name: drbd-module-loader env: - name: LB_HOW value: deps_only
5.13. Using the Host Network for DRBD Replication in Operator v2 Deployments
Instructions in this section will describe how you can use the host network for DRBD replication traffic.
By default, DRBD will use the container network to replicate volume data. This ensures replication works on a wide range of clusters without further configuration. It also enables use of NetworkPolicy
to block unauthorized access to DRBD traffic. Since the network interface of the pod is tied to the lifecycle of the pod, it also means DRBD will temporarily disrupt replication when the LINSTOR satellite pod is restarted.
In contrast, using the host network for DRBD replication will cause replication to work independently of the LINSTOR satellite pod. The host network might also offer better performance than the container network. As a downside, you will have to manually ensure connectivity between nodes on the relevant ports.
To follow the steps in this section, you should be familiar with editing
LinstorSatelliteConfiguration
resources.
|
5.13.1. Configuring DRBD Replication to Use the Host Network
Switching from the default container network to the host network for DRBD replication is possible at any time. Existing DRBD resources will then be reconfigured to use the host network interface.
To configure the host network for the LINSTOR satellite, apply the following YAML configuration to your deployment:
apiVersion: piraeus.io/v1 kind: LinstorSatelliteConfiguration metadata: name: host-network spec: patches: - target: kind: Pod name: satellite patch: | apiVersion: v1 kind: Pod metadata: name: satellite spec: hostNetwork: true
After the satellite pods are recreated, they will use the host network. Any existing DRBD resources are reconfigured to use a new IP address on the host network rather than an IP address on the container network.
5.13.2. Configuring DRBD Replication to Use the Container Network
Switching back from host network to container network involves manually resetting the configured peer addresses used by DRBD. You can do this by rebooting every node, or by manually resetting the addresses by using the drbdadm
CLI command on each node. Each method is described below.
[[s-kubernetes-drbd-replication-switching-from-host-to-container-network-node-rebooting-v2 ===== Rebooting Nodes to Switch DRBD Replication from the Host to the Container Network
First, you need to remove the LinstorSatelliteConfiguration
that set hostNetwork: true
. You can do this by entering the following kubectl
command:
$ kubectl delete linstorsatelliteconfigurations.piraeus.io host-network linstorsatelliteconfiguration.piraeus.io "host-network" deleted
Next, reboot each cluster node, either serially, one by one, or else all at once. In general, replication will not work between rebooted nodes and non-rebooted nodes. The non-rebooted nodes will continue to use the host network addresses, which are generally not reachable from the container network.
After all nodes have restarted, all resources will be configured to use the container network, and all DRBD connections should be connected again.
[[s-kubernetes-drbd-replication-switching-from-host-to-container-network-node-drbdadm-v2 ===== Using the DRBD Administration Tool to Switch DRBD Replication from the Host to the Container Network
During this procedure, ensure that no new volumes or snapshots are created, otherwise the migration to the container network might not be applied to all resources. |
First, you need to temporarily stop all DRBD replication and suspend all DRBD volume I/O operations by using the drbdadm suspend-io all
command. Enter the command once on each LINSTOR satellite pod.
$ kubectl exec node1.example.com -- drbdadm suspend-io all $ kubectl exec node2.example.com -- drbdadm suspend-io all $ kubectl exec node3.example.com -- drbdadm suspend-io all
Next, disconnect all DRBD connections on all nodes.
$ kubectl exec node1.example.com -- drbdadm disconnect --force all $ kubectl exec node2.example.com -- drbdadm disconnect --force all $ kubectl exec node3.example.com -- drbdadm disconnect --force all
Next, you can safely reset all DRBD connection paths. This frees the connection on each node to be moved to the container network.
$ kubectl exec node1.example.com -- drbdadm del-path all $ kubectl exec node2.example.com -- drbdadm del-path all $ kubectl exec node3.example.com -- drbdadm del-path all
Finally, remove the LinstorSatelliteConfiguration
resource configuration that set hostNetwork: true
. This will result in the creation of new LINSTOR satellite pods that use the container network.
$ kubectl delete linstorsatelliteconfigurations.piraeus.io host-network linstorsatelliteconfiguration.piraeus.io "host-network" deleted
After the pods are recreated and the LINSTOR satellites are Online
, the DRBD resource will be reconfigured and resume I/O operations.
5.14. Evacuating a Node in Kubernetes
If you want to evacuate a LINSTOR node of its resources, so that they are placed onto other nodes within your cluster, the process is detailed in Evacuating a Node. However, before evacuating a LINSTOR node in Kubernetes, you need to take an additional action.
First move the node’s workload to another node. You can do this by entering the command:
# kubectl drain --ignore-daemonsets <node_name>
After verifying that your cluster is running as expected, you can continue to follow the steps in Evacuating a Node.
If you are planning on evacuating more than one node, enter the following command on all the nodes that you will be evacuating:
# linstor node set-property n1.k8s-mwa.at.linbit.com AutoplaceTarget false
This ensures that LINSTOR will not place resources from a node that you are evacuating onto another node that you plan on evacuating.
5.15. Monitoring With Prometheus
You can use Prometheus to monitor LINSTOR components.
5.15.1. Monitoring with Prometheus in Operator v1 Deployments
In Operator v1 deployments, the operator will set up monitoring containers along the existing components and make them available as a Service
.
If you use the Prometheus Operator, the LINSTOR Operator will also set up the ServiceMonitor
instances. The metrics will automatically be collected by the Prometheus instance associated to the operator, assuming
watching the Piraeus namespace is enabled.
To disable exporting of metrics, set operator.satelliteSet.monitoringImage
to an empty value.
LINSTOR Controller Monitoring in Operator v1 Deployments
The LINSTOR controller exports cluster-wide metrics. Metrics are exported on the existing controller service, using the
path /metrics
.
DRBD Resource Monitoring in Operator v1 Deployments
All satellites are bundled with a secondary container that uses drbd-reactor
to export metrics directly from DRBD. The metrics are available on port 9942, for convenience a headless service named
<linstorsatelliteset-name>-monitoring
is provided.
If you want to disable the monitoring container, set monitoringImage
to ""
in your LinstorSatelliteSet
resource.
5.16. Upgrading a LINSTOR Deployment on Kubernetes
A LINSTOR deployment on Kubernetes can be upgraded to a new release.
During the upgrade process, attaching, detaching or provisioning of volumes will be paused. Existing volumes and volumes already in use by a pod will continue to work.
5.16.1. Upgrading LINSTOR Operator v2
If you deployed LINSTOR using Operator v2, you can upgrade LINBIT SDS by deploying the newer version of LINSTOR Operator.
During the upgrade process, the LINSTOR satellite pods will restart. This will stop replication of DRBD devices, freezing any writes on volumes, until the satellite pods are online again. |
To upgrade, change the tag referenced in the kustomization file:
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namespace: linbit-sds
resources:
- https://charts.linstor.io/static/v2.2.0.yaml
generatorOptions:
disableNameSuffixHash: true
secretGenerator:
- name: drbdio-pull-secret
type: kubernetes.io/dockerconfigjson
literals:
- .dockerconfigjson={"auths":{"drbd.io":{"username":"MY_LINBIT_USER","password":"MY_LINBIT_PASSWORD"}}}
Then, apply the kustomization.yaml
file, by using the following kubectl
command, and wait for the upgrade to complete:
$ kubectl apply -k . namespace/linbit-sds created [...] $ kubectl -n linbit-sds wait pod --for=condition=Ready --all
5.16.2. Upgrading LINSTOR Operator v1
Before upgrading to a new release, you should ensure you have an up-to-date backup of the LINSTOR database. If you are using the etcd database packaged in the LINSTOR Chart, see here
Upgrades using the LINSTOR etcd deployment require etcd to use persistent storage. Only follow these steps if etcd was deployed using etcd.persistentVolume.enabled=true
|
Upgrades will update to new versions of the following components:
-
LINSTOR Operator deployment
-
LINSTOR Controller
-
LINSTOR Satellite
-
LINSTOR CSI Driver
-
etcd
-
Stork
Some versions require special steps, refer to instructions here The main command to upgrade to a new LINSTOR Operator version is:
helm repo update helm upgrade linstor-op linstor/linstor
If you used any customizations on the initial install, pass the same options to helm upgrade
. The options currently
in use can be retrieved from Helm.
# Retrieve the currently set options $ helm get values linstor-op USER-SUPPLIED VALUES: USER-SUPPLIED VALUES: null drbdRepoCred: drbdiocred operator: satelliteSet: kernelModuleInjectionImage: drbd.io/drbd9-rhel8:v9.0.28 storagePools: lvmThinPools: - devicePaths: - /dev/vdb name: thinpool thinVolume: thinpool volumeGroup: "" # Save current options $ helm get values linstor-op > orig.yaml # modify values here as needed. for example selecting a newer DRBD image $ vim orig.yaml # Start the upgrade $ helm upgrade linstor-op linstor/linstor -f orig.yaml
This triggers the rollout of new pods. After a short wait, all pods should be running and ready. Check that no errors are listed in the status section of LinstorControllers, LinstorSatelliteSets and LinstorCSIDrivers.
5.16.3. Upgrading a LINSTOR Cluster with Kubernetes Back End
The LINSTOR Operator will create a backup of the database before upgrading. This makes it possible to roll back to a known state should something go wrong during the upgrade.
There are situations in which the Operator can’t create the backup automatically. This might be because:
-
The base version of the chart or operator is too old. Automatic backups are available starting with version 1.8.0 If upgrading from a version before 1.8.0, follow the manual steps in the next section.
-
The backup is too large to fit into a Kubernetes secret. In this case an error is reported in the status field of the
LinstorController
resources. Follow the instructions by copying the created backup to a safe location and creating the necessary secret.kubectl cp <linstor-operator-pod>:/run/linstor-backups/linstor-backup-<some-hash>.tar.gz <destination-path> kubectl create secret linstor-backup-<same-hash>
Creating a backup of the LINSTOR Database
Follow these instructions if you need to manually create a backup of the LINSTOR Kubernetes database.
-
Stop the current controller:
$ kubectl patch linstorcontroller linstor-op-cs '{"spec":{"replicas": 0}}' $ kubectl rollout status --watch deployment/linstor-op-cs-controller
-
The following command will create a file
crds.yaml
, which stores the current state of all LINSTOR Custom Resource Definitions:$ kubectl get crds | grep -o ".*.internal.linstor.linbit.com" | \ xargs kubectl get crds -oyaml > crds.yaml
-
In addition to the definitions, the actual resources must be backed up as well:
$ kubectl get crds | grep -o ".*.internal.linstor.linbit.com" | \ xargs -i{} sh -c "kubectl get {} -oyaml > {}.yaml"
-
If upgrading the chart, use
--set IHaveBackedUpAllMyLinstorResources=true
to acknowledge you have executed the above steps.
Restoring From a LINSTOR Database Backup
Follow these instructions if you need to recover from an failure during a LINSTOR upgrade.
-
Fetch the backup (skip if the backup is already available on your local machine):
$ # List the available backups $ kubectl get secret '-ocustom-columns=NAME:.metadata.name,FROM:metadata.annotations.linstor\.linbit\.com/backup-previous-version,CREATED-AT:.metadata.creationTimestamp' $ kubectl get secret linstor-backup-<backup-specific-hash> '-ogo-template=go-template={{index .data ".binaryData.backup.tar.gz" | base64decode}}' > linstor-backup.tar.gz
-
Unpack the backup
$ tar xvf linstor-backup.tar.gz crds.yaml ....
-
Stop the current controller:
$ kubectl patch linstorcontroller linstor-op-cs "{"spec":{"replicas": 0}}" $ kubectl rollout status --watch deployment/piraeus-op-cs-controller
-
Delete existing resources
$ kubectl get crds | grep -o ".*.internal.linstor.linbit.com" | xargs --no-run-if-empty kubectl delete crds
-
Apply the old LINSTOR CRDs
$ kubectl apply -f crds.yaml
-
Apply the old LINSTOR resource state
$ kubectl apply -f *.internal.linstor.linbit.com.yaml
-
Re-apply the helm chart using the old LINSTOR version
$ helm upgrade linstor-op charts/piraeus --set operator.controller.controllerImage=... --set operator.satelliteSet.satelliteImage=...
5.16.4. Upgrading Instructions for Specific Versions
Some versions require special steps, see below.
Upgrading to 1.10
Version 1.10 introduces an option to share DRBD configuration between host and container. If you need this option, you have to update the CRDs. Because Helm does not upgrade CRDs on chart upgrade, instead enter the following commands:
$ helm repo update $ helm pull linstor/linstor --untar $ kubectl replace -f linstor/crds/ customresourcedefinition.apiextensions.k8s.io/linstorcontrollers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorcsidrivers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorsatellitesets.linstor.linbit.com replaced
Upgrading to 1.9
Version 1.9 disables the LINSTOR HA Controller deployment by default. The deployment has moved out of the LINSTOR Operator chart. If you want to keep using the old version, enable it again using this Helm command:
helm upgrade linstor-op linstor/linstor ... --set haController.enabled=true
If you are upgrading to v1.9 from v1.6 or earlier, you need to either:
-
Create a master passphrase, before you upgrade:
$ kubectl create secret generic linstor-pass --from-literal=MASTER_PASSPHRASE=<password>
-
Or, upgrade to v1.7 first, and Helm will create a master passphrase for you automatically. You can view this passphrase later, by entering:
$ kubectl get secret linstor-op-passphrase \ -ogo-template='{{ .data.MASTER_PASSPHRASE | base64decode }}'
Upgrading to v1.8
This upgrade requires a complete rebuild of the K8s database, so upgrades might take longer than normal. |
Version 1.8 introduces new options to centrally set the log level and number of worker threads for the CSI driver. If you need these options, you have to update the CRDs. As Helm does not upgrade CRDs on chart upgrade, instead enter the following commands:
$ helm repo update $ helm pull linstor/linstor --untar $ kubectl replace -f linstor/crds/ customresourcedefinition.apiextensions.k8s.io/linstorcontrollers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorcsidrivers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorsatellitesets.linstor.linbit.com replaced
In addition, 1.8 reworks the way SSL/TLS setups work. Refer to the Securing Operator v1 Deployment section and work through these steps again.
If you are upgrading to v1.8 from v1.6 or earlier, you need to either:
-
Create a master passphrase, before you upgrade:
$ kubectl create secret generic linstor-pass --from-literal=MASTER_PASSPHRASE=<password>
-
Or, upgrade to v1.7 first, and Helm will create a master passphrase for you automatically. You can view this passphrase later, by entering:
$ kubectl get secret linstor-op-passphrase \ -ogo-template='{{ .data.MASTER_PASSPHRASE | base64decode }}'
Upgrading to v1.6
This versions introduces a new option to support Kubernetes distributions which use different state directories than the
default of /var/lib/kubelet
. A notable example is microk8s, which uses /var/snap/microk8s/common/var/lib/kubelet
.
To support this, a small addition to the LinstorCSIDriver
CRD was necessary. As Helm does not upgrade CRDs on chart
upgrade, instead enter the following commands:
$ helm repo update $ helm pull linstor/linstor --untar $ kubectl replace -f linstor/crds/ customresourcedefinition.apiextensions.k8s.io/linstorcontrollers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorcsidrivers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorsatellitesets.linstor.linbit.com replaced
If you do not apply the new CRDs, you will get errors such as the following:
Error: UPGRADE FAILED: error validating "": error validating data: ValidationError(LinstorCSIDriver.spec): unknown field "kubeletPath" in com.linbit.linstor.v1.LinstorCSIDriver.spec
If you previously used the included snapshot-controller to process VolumeSnapshot
resources, you should replace it
with the new charts provided by the Piraeus project. The section on snapshots has
been updated to include instructions on how you can add the snapshot-controller to your cluster.
Upgrading to v1.5
This version introduces a monitoring component for DRBD resources. This requires a new image
and a replacement of the existing LinstorSatelliteSet
CRD. Helm does not upgrade the CRDs on a chart upgrade,
instead enter the following commands:
$ helm repo update $ helm pull linstor/linstor --untar $ kubectl replace -f linstor/crds/ customresourcedefinition.apiextensions.k8s.io/linstorcontrollers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorcsidrivers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorsatellitesets.linstor.linbit.com replaced
If you do not plan to use the provided monitoring you still need to apply the above steps, otherwise you will get an error such as the following:
Error: UPGRADE FAILED: error validating "": error validating data: ValidationError(LinstorSatelliteSet.spec): unknown field "monitoringImage" in com.linbit.linstor.v1.LinstorSatelliteSet.spec
Some Helm versions fail to set the monitoring image even after replacing the CRDs. In that case, the in-cluster
LinstorSatelliteSet will show an empty monitoringImage value. Edit the resource using
kubectl edit linstorsatellitesets and set the value to drbd.io/drbd-reactor:v0.3.0 to enable monitoring.
|
Upgrading to v1.4
This version introduces a new default version for the etcd image, so take extra care that etcd is using persistent storage. Upgrading the etcd image without persistent storage will corrupt the cluster.
If you are upgrading an existing cluster without making use of new Helm options, no additional steps are necessary.
If you plan to use the newly introduced additionalProperties
and additionalEnv
settings, you have to replace
the installed CustomResourceDefinitions with newer versions. Helm does not upgrade the CRDs on a chart upgrade
$ helm pull linstor/linstor --untar $ kubectl replace -f linstor/crds/ customresourcedefinition.apiextensions.k8s.io/linstorcontrollers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorcsidrivers.linstor.linbit.com replaced customresourcedefinition.apiextensions.k8s.io/linstorsatellitesets.linstor.linbit.com replaced
Upgrading to v1.2
LINSTOR Operator v1.2 is supported on Kubernetes 1.17+. If you are using an older Kubernetes distribution, you might need to change the default settings, for example [the CSI provisioner](https://kubernetes-csi.github.io/docs/external-provisioner.html).
There is a known issue when updating the CSI components: the pods will not be updated to the newest image and the
errors
section of the LinstorCSIDrivers resource shows an error updating the DaemonSet. In this case, manually
delete deployment/linstor-op-csi-controller
and daemonset/linstor-op-csi-node
. They will be re-created by the Operator.
6. LINSTOR Volumes in OpenShift
This chapter describes the usage of LINBIT SDS in OpenShift as managed by the LINSTOR Operator and with volumes provisioned using the LINSTOR CSI plugin.
OpenShift is the official Red Hat developed and supported distribution of Kubernetes. The value of OpenShift is the strong integration of otherwise optional components, like network ingress and monitoring, all tied together with a Web UI to manage it all. LINSTOR Operator integrates with these components where possible.
6.1. Deploying LINBIT SDS on OpenShift
Deploying LINBIT SDS on OpenShift is similar to deploying LINBIT SDS on other Kubernetes clusters. As prerequisites, you need:
-
Access to your OpenShift cluster through the
oc
utility. -
Your LINBIT Customer Portal credentials for accessing
drbd.io
.
LINBIT’s container image repository (http://drbd.io) is only available to LINBIT customers or through LINBIT customer trial accounts. Contact LINBIT for information on pricing or to begin a trial. Alternatively, you can use the LINSTOR SDS upstream project, named Piraeus, without being a LINBIT customer. |
First, create a new OpenShift project for LINBIT SDS which will also create a namespace for LINBIT SDS deployment:
$ oc new-project linbit-sds Now using project "linbit-sds" on server ...
Next, create a file named kustomization.yaml
to customize some of the deployment’s default
values:
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namespace: linbit-sds
resources:
- https://charts.linstor.io/static/v2.1.1.yaml
generatorOptions:
disableNameSuffixHash: true
secretGenerator:
- name: drbdio-pull-secret
type: kubernetes.io/dockerconfigjson
literals:
- .dockerconfigjson={"auths":{"drbd.io":{"username":"MY_LINBIT_USER","password":"MY_LINBIT_PASSWORD"}}} (1)
1 | Replace MY_LINBIT_USER and MY_LINBIT_PASSWORD with your LINBIT customer portal
credentials. |
The YAML configuration manifest above is current at the time of writing. Refer to https://charts.linstor.io for the most up-to-date version or previous versions if needed. |
You can make additional modifications to the kustomizaion.yaml
file based on your
preferences and needs. Possible options are discussed in the
Kubernetes advanced deployment section.
Finally, deploy LINBIT SDS by applying the customized configuration, and wait until all pods are
ready, by entering the following commands in the same directory as your kustomization.yaml
:
$ oc apply -k . && \ oc wait --for=condition=ready pod --all -n linbit-sds --timeout=5m && \ oc get pods -n linbit-sds
Output should eventually show that a LINSTOR controller pod is up and running.
NAME READY STATUS RESTARTS AGE linstor-operator-controller-manager-59586c7bb5-qlfwb 1/1 Running 0 11s
After deploying the LINSTOR controller pod, enter the following command to complete the deployment of your LINBIT SDS in OpenShift cluster:
# oc apply -f - <<EOF apiVersion: piraeus.io/v1 kind: LinstorCluster metadata: name: linstorcluster spec: {} EOF # oc wait pod --for=condition=Ready -n linbit-sds --timeout=5m --all
Output should eventually show that your LINBIT SDS cluster pods are up and running.
NAME READY STATUS RESTARTS AGE ha-controller-6fl6b 1/1 Running 0 60s ha-controller-c955w 1/1 Running 0 60s ha-controller-v4mdr 1/1 Running 0 60s kube-0 2/2 Running 0 56s (1) kube-1 2/2 Running 0 56s (1) kube-2 2/2 Running 0 55s (1) linstor-controller-779bffbc59-6jjzd 1/1 Running 0 61s linstor-csi-controller-8cd45658f-6f9t6 7/7 Running 0 61s linstor-csi-node-blgk8 3/3 Running 0 61s linstor-csi-node-mn8p6 3/3 Running 0 61s linstor-csi-node-pncpz 3/3 Running 0 61s linstor-operator-controller-manager-59586c7bb5-qlfwb 1/1 Running 0 4m2s
1 | These pods are the LINSTOR satellite node pods. The pod name reflects each node’s hostname. |
6.1.2. Configuring LINBIT GUI Access
The LINSTOR container images come with the LINBIT GUI preinstalled. To expose it on your cluster, configure an OpenShift Route resource:
$ oc create route edge --service linstor-op-cs $ oc get route NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD linstor-op-cs linstor-op-cs-storage.apps.oc.example.com linstor-op-cs linstor-op-cs edge None
The GUI is now accessible at https://linstor-op-cs-storage.apps.oc.example.com/ui/
This might enable external access to LINBIT GUI and LINSTOR API. Ensure that only authorized users can access it, for example, by requiring client side TLS certificates on the route. |
6.1.3. Configuring Cluster Monitoring
OpenShift includes a fully configured monitoring stack. While most of the monitoring stack is only intended for OpenStack infrastructure, basic monitoring for LINBIT SDS is possible.
First, ensure that monitoring of user-defined projects is enabled in OpenShift by following the steps in Red Hat documentation.
Once monitoring for user-defined projects is enabled, the LINSTOR Operator
automatically detects the presence of OpenShift’s Prometheus-based monitoring
stack and configures the ServiceMonitor
resources. The Prometheus instance
will scrape metrics for DRBD and LINSTOR from all Cluster nodes.
6.2. Interacting with LINBIT SDS in OpenShift
The LINSTOR Controller pod includes a LINSTOR Client, making it easy to access LINSTOR’s interactive mode. For instance:
$ oc exec -it deployment/linstor-op-cs-controller -- linstor interactive LINSTOR ==> ...
This should only be necessary for investigating problems and accessing advanced functionality. Regular operation such as creating volumes should be achieved through the Kubernetes integration.
7. LINSTOR Volumes in Nomad
This chapter describes using LINSTOR and DRBD to provision volumes in Nomad.
7.1. Introduction to Nomad
Nomad is a simple and flexible workload orchestrator to deploy and manage containers and non-containerized applications across on-premises and cloud environments.
Nomad supports provisioning storage volumes using plug-ins conforming to the Container Storage Interface (CSI).
LINBIT distributes a CSI plug-in in the form of container images from drbd.io. The plug-in can be configured to work with a LINSTOR cluster that is deployed along or inside a Nomad cluster.
LINBIT’s container image repository (http://drbd.io) is only available to LINBIT customers or through LINBIT customer trial accounts. Contact LINBIT for information on pricing or to begin a trial. Alternatively, you may use LINSTOR SDS’ upstream project named Piraeus, without being a LINBIT customer. |
7.2. Deploying LINSTOR on Nomad
This section describes how you can deploy and configure a new LINSTOR cluster in Nomad.
If you want to install LINSTOR directly on your nodes, check out the guide on installing LINSTOR. You can skip this section and jump directly to deploying the CSI driver. |
7.2.1. Preparing Nomad
To run LINSTOR, every Nomad agent needs to be configured to:
-
Support the docker driver and allow executing privileged containers
To allow running privileged containers, add the following snippet to your Nomad agent configuration and restart Nomad
Listing 15. /etc/nomad.d/docker-privileged.hclplugin "docker" { config { allow_privileged = true } }
-
Support for container networking. If you don’t have the Container Network Interface plug-ins installed, you will only be able to use
mode = "host"
in your job networks. For most production setups, we recommend installing the default plug-ins:Head to the plug-in release page, select the release archive appropriate for your distribution and unpack them in
/opt/cni/bin
. You might need to create the directory before unpacking. -
Provide a host volume, allowing a container access to the hosts
/dev
directoryTo create a host volume, add the following snippet to your Nomad agent configuration and restart Nomad.
Listing 16. /etc/nomad.d/host-volume-dev.hclclient { host_volume "dev" { path = "/dev" } }
7.2.2. Creating a LINSTOR Controller Job
The LINSTOR Controller is deployed as a service with no replicas. At any point in time, there can only be one LINSTOR Controller running in a cluster. It is possible to restart the controller on a new node, provided it still has access to the database. See Creating a Highly Available LINSTOR Cluster for more information.
The following example will create a Nomad job starting a single LINSTOR Controller in datacenter dc1
and connect
to an external database.
job "linstor-controller" {
datacenters = ["dc1"] (1)
type = "service"
group "linstor-controller" {
network {
mode = "bridge"
# port "linstor-api" { (2)
# static = 3370
# to = 3370
# }
}
service { (3)
name = "linstor-api"
port = "3370"
connect {
sidecar_service {}
}
check {
expose = true
type = "http"
name = "api-health"
path = "/health"
interval = "30s"
timeout = "5s"
}
}
task "linstor-controller" {
driver = "docker"
config {
image = "drbd.io/linstor-controller:v1.13.0" (4)
auth { (5)
username = "example"
password = "example"
server_address = "drbd.io"
}
mount {
type = "bind"
source = "local"
target = "/etc/linstor"
}
}
# template { (6)
# destination = "local/linstor.toml"
# data = <<EOH
# [db]
# user = "example"
# password = "example"
# connection_url = "jdbc:postgresql://postgres.internal.example.com/linstor"
# EOH
# }
resources {
cpu = 500 # 500 MHz
memory = 700 # 700MB
}
}
}
}
1 | Replace dc1 with your own data center name |
||
2 | This exposes the LINSTOR API on the host on port 3370 .
|
||
3 | The service block is used to expose the LINSTOR API to other jobs through the service mesh.
|
||
4 | This sets the LINSTOR Controller image to run. The latest images are available from
drbd.io.
|
||
5 | Sets the authentication to use when pulling the image. If pulling from drbd.io , you need
to use your LINBIT customer login here. Read more about pulling from a private repo
here. |
||
6 | This template can be used to set arbitrary configuration options for LINSTOR. This example configures an external database for LINSTOR. You can find a more detailed explanation of LINSTOR’s database options here and more on Nomad templates here. |
Apply the job by running:
$ nomad job run linstor-controller.hcl
==> Monitoring evaluation "7d8911a7"
Evaluation triggered by job "linstor-controller"
==> Monitoring evaluation "7d8911a7"
Evaluation within deployment: "436f4b2d"
Allocation "0b564c73" created: node "07754224", group "controller"
Evaluation status changed: "pending" -> "complete"
==> Evaluation "7d8911a7" finished with status "complete"
Using a Host Volume for LINSTOR’s Database
If you want to try LINSTOR without setting up an external database, you can make use of LINSTOR’s built-in filesystem based database. To make the database persistent, you need to ensure it is placed on a host volume.
Using a host volume means that only a single node is able to run the LINSTOR Controller. If the node is unavailable, the LINSTOR Cluster will also be unavailable. For alternatives, use an external (highly available) database or deploy the LINSTOR cluster directly on the hosts. |
To create a host volume for the LINSTOR database, first create the directory on the host with the expected permissions
$ mkdir -p /var/lib/linstor
$ chown -R 1000:0 /var/lib/linstor
Then add the following snippet to your Nomad agent configuration and restart Nomad
client {
host_volume "linstor-db" {
path = "/var/lib/linstor"
}
}
Then, add the following snippets to the linstor-controller.hcl
example from above and adapt the connection_url
option from the configuration template.
job > group
volume "linstor-db" {
type = "host"
source = "linstor-db"
}
job > group > task
volume_mount {
volume = "linstor-db"
destination = "/var/lib/linstor"
}
template {
destination = "local/linstor.toml"
data = <<EOH
[db]
user = "linstor"
password = "linstor"
connection_url = "jdbc:h2:/var/lib/linstor/linstordb"
EOH
}
7.2.3. Creating a LINSTOR Satellite Job
In Nomad, the LINSTOR satellites are deployed as a system job that runs in a privileged container. In addition to the satellites, the job will also load the DRBD module along with other kernel modules used by LINSTOR.
The following example will create a Nomad job starting a LINSTOR satellite on every node in data center dc1
.
job "linstor-satellite" {
datacenters = ["dc1"] (1)
type = "system"
group "satellite" {
network {
mode = "host"
}
volume "dev" { (2)
type = "host"
source = "dev"
}
task "linstor-satellite" {
driver = "docker"
config {
image = "drbd.io/linstor-satellite:v1.13.0" (3)
auth { (4)
username = "example"
password = "example"
server_address = "drbd.io"
}
privileged = true (5)
network_mode = "host" (6)
}
volume_mount { (2)
volume = "dev"
destination = "/dev"
}
resources {
cpu = 500 # 500 MHz
memory = 500 # 500MB
}
}
task "drbd-loader" {
driver = "docker"
lifecycle {
hook = "prestart" (7)
}
config {
image = "drbd.io/drbd9-rhel8:v9.0.29" (8)
privileged = true (5)
auth { (4)
username = "example"
password = "example"
server_address = "drbd.io"
}
}
env {
LB_HOW = "shipped_modules" (9)
}
volume_mount { (10)
volume = "kernel-src"
destination = "/usr/src"
}
volume_mount { (10)
volume = "modules"
destination = "/lib/modules"
}
}
volume "modules" { (10)
type = "host"
source = "modules"
read_only = true
}
volume "kernel-src" { (10)
type = "host"
source = "kernel-src"
read_only = true
}
}
}
1 | Replace dc1 with your own data center name. |
||
2 | The dev host volume is the volume created in Preparing Nomad, which allows the
satellite to manage the hosts block devices. |
||
3 | This sets the LINSTOR Satellite image to run. The latest images are available from
drbd.io. The satellite image version has to match the version of the controller
image.
|
||
4 | Sets the authentication to use when pulling the image. If pulling from drbd.io , you need
to use your LINBIT customer login here. Read more about pulling from a private repo
here. |
||
5 | To configure storage devices, DRBD and load kernel modules, the containers need to be running in privileged mode. | ||
6 | The satellite needs to communicate with DRBD, which requires access to the netlink interface running in the hosts network. | ||
7 | The drbd-loader task will be executed once at the start of the satellite and load DRBD and
other useful kernel modules. |
||
8 | The drbd-loader is specific to the distribution you are using. Available options are:
|
||
9 | The drbd-loader container can be configured using environment variables. LB_HOW tells the
container how to insert the DRBD kernel module. Available options are:
|
||
10 | In order for the drbd-loader container to build DRBD or load existing modules, it needs
access to a hosts /usr/src and /lib/modules respectively.
This requires setting up additional host volumes on every node. The following snippet needs to be added to every Nomad agent confiration, then Nomad needs to be restarted. Listing 22. /etc/nomad.d/drbd-loader-volumes.hcl
|
Apply the job by running:
$ nomad job run linstor-satellite.hcl
==> Monitoring evaluation "0c07469d"
Evaluation triggered by job "linstor-satellite"
==> Monitoring evaluation "0c07469d"
Evaluation status changed: "pending" -> "complete"
==> Evaluation "0c07469d" finished with status "complete"
7.2.4. Configuring LINSTOR in Nomad
Once the linstor-controller
and linstor-satellite
jobs are running, you can start configuring the cluster using
the linstor
command line tool.
This can done:
-
directly by
nomad exec
-ing into thelinstor-controller
container. -
using the
drbd.io/linstor-client
container on the host running thelinstor-controller
:docker run -it --rm --net=host drbd.io/linstor-client node create
-
by installing the
linstor-client
package on the host running thelinstor-controller
.
In all cases, you need to add the satellites to your cluster and
create some storage pools. For example, to add the node nomad-01.example.com
and configure
a LVM Thin storage pool, you would run:
$ linstor node create nomad-01.example.com
$ linstor storage-pool create lvmthin nomad-01.example.com thinpool linstor_vg/thinpool
The CSI driver requires your satellites to be named after their hostname. To be precise, the satellite name
needs to match Nomads attr.unique.hostname attribute on the node.
|
7.3. Deploying the LINSTOR CSI Driver in Nomad
The CSI driver is deployed as a system job, meaning it runs on every node in the cluster.
The following example will create a Nomad job starting a LINSTOR CSI Driver on every node in data center dc1
.
job "linstor-csi" {
datacenters = ["dc1"] (1)
type = "system"
group "csi" {
network {
mode = "bridge"
}
service {
connect {
sidecar_service { (2)
proxy {
upstreams {
destination_name = "linstor-api"
local_bind_port = 8080
}
}
}
}
}
task "csi-plugin" {
driver = "docker"
config {
image = "drbd.io/linstor-csi:v0.13.1" (3)
auth { (4)
username = "example"
password = "example"
server_address = "drbd.io"
}
args = [
"--csi-endpoint=unix://csi/csi.sock",
"--node=${attr.unique.hostname}", (5)
"--linstor-endpoint=http://${NOMAD_UPSTREAM_ADDR_linstor_api}", (6)
"--log-level=info"
]
privileged = true (7)
}
csi_plugin { (8)
id = "linstor.csi.linbit.com"
type = "monolith"
mount_dir = "/csi"
}
resources {
cpu = 100 # 100 MHz
memory = 200 # 200MB
}
}
}
}
1 | Replace dc1 with your own data center name |
||
2 | The sidecar_service stanza enables use of the service mesh generated by using
Consul Connect. If you have not configured this feature in Nomad, or you are
using an external LINSTOR Controller, you can skip this configuration. |
||
3 | This sets the LINSTOR CSI Driver image to run. The latest images are available from drbd.io.
|
||
4 | Sets the authentication to use when pulling the image. If pulling from drbd.io , you need
to use your LINBIT customer login here. Read more about pulling from a private repo
here. |
||
5 | This argument sets the node name used by the CSI driver to identify itself in the LINSTOR API. By default, this is set to the node’s hostname. | ||
6 | This argument sets the LINSTOR API endpoint. If you are not using the consul service mesh (see Nr. 2 above), this needs to be set to the Controllers API endpoint. The endpoint needs to be reachable from every node this is deployed on. | ||
7 | The CSI driver needs to execute mount commands, requiring privileged containers. | ||
8 | The csi_plugin stanza informs Nomad that this task is a CSI plug-in. The Nomad agent will
forward requests for volumes to one of the jobs containers. |
Apply the job by running:
$ nomad job run linstor-csi.hcl
==> Monitoring evaluation "0119f19c"
Evaluation triggered by job "linstor-csi"
==> Monitoring evaluation "0119f19c"
Evaluation status changed: "pending" -> "complete"
==> Evaluation "0119f19c" finished with status "complete"
7.4. Using LINSTOR Volumes in Nomad
Volumes in Nomad are created using a volume-specification.
As an example, the following specification requests a 1GiB volume with 2 replicas from the LINSTOR storage pool thinpool
.
id = "vol1" (1)
name = "vol1" (2)
type = "csi"
plugin_id = "linstor.csi.linbit.com"
capacity_min = "1GiB"
capacity_max = "1GiB"
capability {
access_mode = "single-node-writer" (3)
attachment_mode = "file-system" (4)
}
mount_options {
fs_type = "ext4" (5)
}
parameters { (6)
"resourceGroup" = "default-resource",
"storagePool" = "thinpool",
"autoPlace" = "2"
}
1 | The id is used to reference this volume in Nomad. Used in the volume.source field of a
job specification. |
2 | The name is used when creating the volume in the back end (that is, LINSTOR). Ideally this
matches the id and is a valid LINSTOR resource name. If the name would not be valid, LINSTOR
CSI will generate a random compatible name. |
3 | What kind of access the volume should support. LINSTOR CSI supports:
|
4 | Can be file-system or block-device . |
5 | Specify the file system to use. LINSTOR CSI supports ext4 and xfs . |
6 | Additional parameters to pass to LINSTOR CSI. The example above requests the resource be
part of the default-resource resource group and should deploy 2
replicas.
For a complete list of available parameters, you can check out the guide on Kubernetes storage classes. Kubernetes, like Nomad, makes use of the CSI plug-in. |
To create the volume, run the following command:
$ nomad volume create vol1.hcl
Created external volume vol1 with ID vol1
$ nomad volume status
Container Storage Interface
ID Name Plugin ID Schedulable Access Mode
vol1 vol1 linstor.csi.linbit.com true <none>
$ linstor resource list
╭──────────────────────────────────────────────────────────────────────────────────────────────╮
┊ ResourceName ┊ Node ┊ Port ┊ Usage ┊ Conns ┊ State ┊ CreatedOn ┊
╞══════════════════════════════════════════════════════════════════════════════════════════════╡
┊ vol1 ┊ nomad-01.example.com ┊ 7000 ┊ Unused ┊ Ok ┊ UpToDate ┊ 2021-06-15 14:56:32 ┊
┊ vol1 ┊ nomad-02.example.com ┊ 7000 ┊ Unused ┊ Ok ┊ UpToDate ┊ 2021-06-15 14:56:32 ┊
╰──────────────────────────────────────────────────────────────────────────────────────────────╯
7.4.1. Using Volumes in Jobs
To use the volume in a job, add the volume
and volume_mount
stanzas to the job specification:
job "example" {
...
group "example" {
volume "example-vol" {
type = "csi"
source = "vol1"
attachment_mode = "file-system"
access_mode = "single-node-writer"
}
task "mount-example" {
volume_mount {
volume = "example-vol"
destination = "/data"
}
...
}
}
}
7.4.2. Creating Snapshots of Volumes
LINSTOR can create snapshots of existing volumes, provided the underlying storage pool driver supports snapshots.
The following command creates a snapshot named snap1
of the volume vol1
.
$ nomad volume snapshot create vol1 snap1
Snapshot ID Volume ID Size Create Time Ready?
snap1 vol1 1.0 GiB None true
$ linstor s l
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
┊ ResourceName ┊ SnapshotName ┊ NodeNames ┊ Volumes ┊ CreatedOn ┊ State ┊
╞════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╡
┊ vol1 ┊ snap1 ┊ nomad-01.example.com, nomad-02.example.com ┊ 0: 1 GiB ┊ 2021-06-15 15:04:10 ┊ Successful ┊
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
You can use a snapshot to pre-populate an existing volume with data from the snapshot
$ cat vol2.hcl
id = "vol2"
name = "vol2"
snapshot_id = "snap1"
type = "csi"
plugin_id = "linstor.csi.linbit.com"
...
$ nomad volume create vol2.hcl
Created external volume vol2 with ID vol2
8. LINSTOR Volumes in Proxmox VE
This chapter describes DRBD in Proxmox Virtual Environment (VE) using the LINSTOR Proxmox Plug-in.
8.1. Introduction to Proxmox VE
Proxmox VE is an easy to use, complete server virtualization environment with KVM, Linux Containers and HA.
‘linstor-proxmox’ is a Perl plugin for Proxmox that, in combination with LINSTOR, allows you to replicate VM disks on several Proxmox VE nodes. This allows to live-migrate active VMs within a few seconds and with no downtime without needing a central SAN, as the data is already replicated to multiple nodes.
8.2. Upgrading Proxmox
If this is a fresh installation, skip this section and continue with Installing the LINSTOR Proxmox Plug-in.
8.2.1. Upgrading Plug-in to 7.x
Version 7 of the plugin uses a LINSTOR controller API that is available from LINSTOR version 1.21.1 onwards. Make sure that your LINSTOR setup (controller and satellites) use at least that version.
8.2.2. Upgrading Plug-in from 4.x to 5.x
Version 5 of the plugin drops compatibility with the legacy configuration options “storagepool” and “redundancy”. Version 5 requires a “resourcegroup” option, and obviously a LINSTOR resource group. The old options should be removed from the configuration.
Configuring LINSTOR is described in Section Configuring LINSTOR, a typical example follows:
Let’s assume the pool was set to “mypool”, and redundancy to 3.
# linstor resource-group create --storage-pool=mypool --place-count=3 drbdMypoolThree # linstor volume-group create drbdMypoolThree # vi /etc/pve/storage.cfg drbd: drbdstorage content images,rootdir controller 10.11.12.13 resourcegroup drbdMypoolThree
8.2.3. Upgrading Plug-in from 5.x to 6.x
Version 6.0.0 of the plugin drops all code related to the redundancy
setting. This is handled by LINSTOR
resource groups (resourcegroup
setting) for a very long time. No change should be required.
The controllervm
setting, which was intended for executing a LINSTOR controller in a VM manged by LINSTOR is
gone. Using drbd-reactor
to realize a highly available LINSTOR controller is what we suggest.
The settings statuscache
and preferlocal
are now enabled by default.
8.2.4. Upgrading PVE from 5.x to 6.x
With version 6 PVE added additional parameters to some functions and rightfully reset their “APIAGE”. This means that old plugins, while actually usable as they don’t use any of these changed functions do not work anymore. Please upgrade to plugin version 5.2.1 at least.
8.3. Installing the LINSTOR Proxmox Plug-in
To use LINSTOR in Proxmox, you will need to install the LINSTOR Proxmox plugin.
8.3.1. Installing the Proxmox VE Kernel Headers
To use LINSTOR in Proxmox, you will need to install the DRBD kernel module. The DRBD 9 kernel
module is installed as a kernel module source package (drbd-dkms
). Therefore, you will have
to install the Proxmox VE kernel headers package, pve-headers
, before you install the DRBD
kernel module from LINBIT’s repositories. Following that order ensures that the kernel module
will build properly for your kernel.
If you do not plan to install the latest Proxmox kernel, you have to install kernel headers
matching your current running kernel (for example, pve-headers-$(uname -r)
). If you missed
this step, then you can still rebuild the drbd-dkms
package against your current kernel (so
long as you have installed kernel headers in advance) by entering the apt install --reinstall
drbd-dkms
command.
You will need to add the Proxmox PVE repository to your APT sources list,
/etc/apt/sources.list , and then enter apt update , before you can install the pve-headers
package. Refer to
the Proxmox wiki
for instructions.
|
8.3.2. Installing the Proxmox Plug-in By Using LINBIT Customer Repositories
If you are a LINBIT customer, or you have an evaluation account, you can enable LINBIT’s
drbd-9
repository on your node and then update your repositories by using an apt update
command.
You can then install the DRBD kernel module, DRBD utilities, and the LINSTOR Proxmox plugin by entering:
# apt install drbd-utils linstor-proxmox drbd-dkms
Refer to the Using a Script to Manage LINBIT Cluster Nodes for instructions on registering a node with LINBIT and enabling LINBIT repositories. |
8.3.3. Installing the Proxmox Plug-in By Using LINBIT Public Repositories
LINBIT provides a dedicated public repository for Proxmox VE users. This repository not only contains the Proxmox plugin, but the whole DRBD SDS stack including a DRBD SDS kernel module and user-space utilities.
You can add LINBIT’s public repository by entering the commands below, setting $PVERS
to your
Proxmox VE major version (for example, “7”, not “7.1”):
# wget -O /tmp/package-signing-pubkey.asc \ https://packages.linbit.com/package-signing-pubkey.asc # gpg --yes -o /etc/apt/trusted.gpg.d/linbit-keyring.gpg --dearmor \ /tmp/package-signing-pubkey.asc # PVERS=7 && echo "deb [signed-by=/etc/apt/trusted.gpg.d/linbit-keyring.gpg] \ http://packages.linbit.com/public/ proxmox-$PVERS drbd-9" > /etc/apt/sources.list.d/linbit.list
After adding the LINBIT package repository, you can install the Proxmox plugin and other necessary components (DRBD kernel module and utilities), by entering the following command:
# apt update && apt -y install drbd-dkms drbd-utils linstor-proxmox
8.4. Configuring LINSTOR
For the rest of this guide we assume that you have a LINSTOR cluster configured as described in
Initializing Your Cluster. Start the “linstor-controller” on one node, and the “linstor-satellite” on all
nodes. The “linstor-satellite” service needs some extra configuration which should be done via
systemctl edit linstor-satellite.service
:
[Service] Type=notify TimeoutStartSec=infinity
The preferred way to use the plugin, starting from version 4.1.0, is through LINSTOR resource groups and a single volume group within every resource group. LINSTOR resource groups are described in Using Resource Groups to Deploy LINSTOR Provisioned Volumes. All the required LINSTOR configuration (e.g., redundancy count) has to be set on the resource group.
8.5. Configuring the Proxmox Plug-in
The final step is to provide a configuration for Proxmox itself. This can be done by adding an entry in the
/etc/pve/storage.cfg
file, with a content similar to the following.
drbd: drbdstorage content images,rootdir controller 10.11.12.13 resourcegroup defaultpool
The “drbd” entry is fixed and you are not allowed to modify it, as it tells to Proxmox to use DRBD as storage back end. The “drbdstorage” entry can be modified and is used as a friendly name that will be shown in the PVE web GUI to locate the DRBD storage. The “content” entry is also fixed, so do not change it. The redundancy (specified in the resource group) specifies how many replicas of the data will be stored in the cluster. The recommendation is to set it to 2 or 3 depending on your setup. The data is accessible from all nodes, even if some of them do not have local copies of the data. For example, in a 5 node cluster, all nodes will be able to access 3 copies of the data, no matter where they are stored in. The “controller” parameter must be set to the IP of the node that runs the LINSTOR controller service. Only one node can be set to run as LINSTOR controller at the same time. If that node fails, start the LINSTOR controller on another node and change that value to its IP address.
A configuration using different storage pools in different resource groups would look like this:
drbd: drbdstorage content images,rootdir controller 10.11.12.13 resourcegroup defaultpool drbd: fastdrbd content images,rootdir controller 10.11.12.13 resourcegroup ssd drbd: slowdrbd content images,rootdir controller 10.11.12.13 resourcegroup backup
By now, you should be able to create VMs using Proxmox’s web GUI by selecting “drbdstorage“, or any other of the defined pools as storage location.
Starting from version 5 of the plugin, you can set the option “preferlocal yes”. If it is set, the plugin tries to create a diskful assignment on the node that issued the storage create command. With this option you can ensure that the VM gets local storage if possible. Without that option LINSTOR might place the storage on nodes ‘B’ and ‘C’, while the VM is initially started on node ‘A’. This would still work as node ‘A’ then would get a diskless assignment, but having local storage might be preferred.
At this point you can try to live migrate the VM – as all data is accessible on all nodes (even on Diskless nodes) – it will take just a few seconds. The overall process might take a bit longer if the VM is under load and if there is a significant amount of RAM being dirtied all the time. But in any case, the downtime should be minimal and you will see no interruption at all.
Option | Meaning |
---|---|
|
The IP of the LINSTOR controller (‘,’ separated list allowed) |
|
The name of a LINSTOR resource group which defines the deployment of new VMs. As described above |
|
Prefer to create local storage (yes/no). As decribed above |
|
Time in seconds status information is cached, 0 means no extra cache. Relevant on huge clusters with hundreds of resources. This has to be set on all |
|
Path to the client certificate |
|
Path to the client private key |
|
Path to the CA certificate |
8.6. Making the Controller Highly Available (Optional Configuration)
Making LINSTOR highly available is a matter of making the LINSTOR controller highly-available. This step is described in Section Creating a Highly Available LINSTOR Cluster.
The last — but crucial — step is to configure the Proxmox plugin to be
able to connect to multiple LINSTOR controllers. It will use the first one it
receives an answer from. This is done by adding a comma-separated list of
controllers in the controller
section of the plugin like this:
drbd: drbdstorage content images,rootdir controller 10.11.12.13,10.11.12.14,10.11.12.15 resourcegroup defaultpool
9. LINSTOR Volumes in OpenNebula
This chapter describes DRBD in OpenNebula using the LINSTOR storage driver add-on.
Detailed installation and configuration instructions and be found in the README.md file of the driver’s source.
9.1. Introduction to OpenNebula
OpenNebula is a flexible and open source cloud management platform which allows its functionality to be extended using add-ons.
The LINSTOR add-on allows the deployment of virtual machines with highly available images backed by DRBD and attached across the network through DRBD’s own transport protocol.
9.2. Installing the OpenNebula Add-on
Installation of the LINSTOR storage add-on for OpenNebula requires a working OpenNebula cluster as well as a working LINSTOR cluster.
With access to LINBIT’s customer repositories you can install the linstor-opennebula package with:
# apt install linstor-opennebula
or
# yum install linstor-opennebula
Without access to LINBIT’s prepared packages you need to fall back to instructions on the OpenNebula LINSTOR Add-on GitHub page.
A DRBD cluster with LINSTOR can be installed and configured by following the instructions in this guide, see Initializing Your Cluster.
The OpenNebula and DRBD clusters can be somewhat independent of one another with the following exception: OpenNebula’s Front-End and Host nodes must be included in both clusters.
Host nodes do not need a local LINSTOR storage pool, as virtual machine images are attached to them across the network [5].
9.3. Deployment Options
It is recommended to use LINSTOR resource groups to configure the deployment how you like it, see Creating Resource Groups. Previous auto-place and deployment nodes modes are deprecated.
9.4. Configuring the OpenNebula Add-on
9.4.1. Adding the Driver to OpenNebula
Modify the following sections of /etc/one/oned.conf
Add linstor to the list of drivers in the TM_MAD
and DATASTORE_MAD
sections:
TM_MAD = [ EXECUTABLE = "one_tm", ARGUMENTS = "-t 15 -d dummy,lvm,shared,fs_lvm,qcow2,ssh,vmfs,ceph,linstor" ]
DATASTORE_MAD = [ EXECUTABLE = "one_datastore", ARGUMENTS = "-t 15 -d dummy,fs,lvm,ceph,dev,iscsi_libvirt,vcenter,linstor -s shared,ssh,ceph,fs_lvm,qcow2,linstor" ]
linstor is specified twice in the DATASTORE_MAD arguments.
|
Add new TM_MAD_CONF and DS_MAD_CONF sections:
TM_MAD_CONF = [ NAME = "linstor", LN_TARGET = "NONE", CLONE_TARGET = "SELF", SHARED = "yes", ALLOW_ORPHANS="yes", TM_MAD_SYSTEM = "ssh,shared", LN_TARGET_SSH = "NONE", CLONE_TARGET_SSH = "SELF", DISK_TYPE_SSH = "BLOCK", LN_TARGET_SHARED = "NONE", CLONE_TARGET_SHARED = "SELF", DISK_TYPE_SHARED = "BLOCK" ]
DS_MAD_CONF = [ NAME = "linstor", REQUIRED_ATTRS = "BRIDGE_LIST", PERSISTENT_ONLY = "NO", MARKETPLACE_ACTIONS = "export" ]
After making these changes, restart the OpenNebula service.
9.4.2. Configuring the Nodes
The Front-End node issues commands to the Storage and Host nodes through LINSTOR.
Storage nodes hold disk images of VMs locally.
Host nodes are responsible for running instantiated VMs and typically have the storage for the images they need attached across the network through LINSTOR diskless mode.
All nodes must have DRBD9 and LINSTOR installed. This process is detailed in the User’s Guide for DRBD9
It is possible to have Front-End and Host nodes act as storage nodes in addition to their primary role provided that they the meet all the requirements for both roles.
Configuring the Front-end Node
Please verify that the control node(s) that you hope to communicate with are
reachable from the front-end node. linstor node list
for locally running
LINSTOR controllers and linstor --controllers "<IP:PORT>" node list
for
remotely running LINSTOR Controllers is a handy way to test this.
Configuring Host Nodes
Host nodes must have LINSTOR satellite processes running on them and be members
of the same LINSTOR cluster as the Front-End and Storage nodes, and may optionally
have storage locally. If the oneadmin
user is able to passwordlessly SSH between
hosts then live migration may be used with the even with the SSH system datastore.
Configuring Storage Nodes
Only the front-end and host nodes require OpenNebula to be installed, but the
oneadmin
user must be able to passwordlessly access storage nodes. Refer to
the OpenNebula installation guide for your distribution on how to manually
configure the oneadmin
user account.
The storage nodes must use storage pools created with a driver that’s capable of making snapshots, such as the thin LVM plug-in.
In this example preparation of thin-provisioned storage using LVM for LINSTOR, you must create a volume group and thinLV using LVM on each storage node.
The following is an example of this process using two physical volumes (/dev/sdX and /dev/sdY) and generic names for the volume group and thinpool. Take care to set the thinLV’s metadata volume to a reasonable size. once it becomes full it can be difficult to resize.
pvcreate /dev/sdX /dev/sdY vgcreate drbdpool /dev/sdX /dev/sdY lvcreate -l 95%VG --poolmetadatasize 8g -T /dev/drbdpool/drbdthinpool
Then you’ll create storage pool(s) on LINSTOR using this as the backing storage.
If you are using ZFS storage pools or thick-LVM, please use LINSTOR_CLONE_MODE copy
otherwise you will have problems deleting linstor resources, because of ZFS parent-child snapshot
relationships.
|
9.4.3. Permissions for the Administrative Account
The oneadmin
, “Cloud Administrator”, user account must have passwordless sudo access to the mkfs
command on
the Storage nodes
oneadmin ALL=(root) NOPASSWD: /sbin/mkfs
Groups
Be sure to consider the groups that oneadmin
should be added to to
gain access to the devices and programs needed to access storage and
instantiate VMs. For this add-on, the oneadmin
user must belong to the disk
group on all nodes to access the DRBD devices where images are held.
usermod -a -G disk oneadmin
9.4.4. Creating a New LINSTOR Datastore
Create a datastore configuration file named ds.conf and use the onedatastore
tool to create a new datastore based on that configuration. There are two
mutually exclusive deployment options: LINSTOR_AUTO_PLACE and
LINSTOR_DEPLOYMENT_NODES. If both are configured, LINSTOR_AUTO_PLACE is ignored.
For both of these options, BRIDGE_LIST must be a space
separated list of all storage nodes in the LINSTOR cluster.
9.4.5. Creating Resource Groups
Since version 1.0.0 LINSTOR supports resource groups. A resource group is a centralized point for settings that all resources linked to that resource group share.
Create a resource group and volume group for your datastore, it is mandatory to specify a storage-pool
within the resource group, otherwise monitoring space for OpenNebula will not work.
Here we create one with 2 node redundancy and use a created opennebula-storagepool
:
linstor resource-group create OneRscGrp --place-count 2 --storage-pool opennebula-storagepool linstor volume-group create OneRscGrp
Now add a OpenNebula datastore using the LINSTOR plug-in:
cat >ds.conf <<EOI NAME = linstor_datastore DS_MAD = linstor TM_MAD = linstor TYPE = IMAGE_DS DISK_TYPE = BLOCK LINSTOR_RESOURCE_GROUP = "OneRscGrp" COMPATIBLE_SYS_DS = 0 BRIDGE_LIST = "alice bob charlie" #node names EOI onedatastore create ds.conf
9.4.6. Plug-in Attributes
9.4.7. Deprecated Attributes
The following attributes are deprecated and were removed in version 2.0.
LINSTOR_CLONE_MODE
LINSTOR now automatically decides which clone mode it should use.
LINSTOR supports two different clone modes: snapshot
and copy
. These modes are set through the LINSTOR_CLONE_MODE
attribute.
The default mode is snapshot
. It uses a linstor snapshot and restores a new resource from this snapshot, which is then a clone of the image. This mode is usually faster than using the copy
mode as snapshots are cheap copies.
The second mode is copy
. It creates a new resource with the same size as the original and copies the data with dd
to the new resource. This mode will be slower than snapshot
, but is more robust as it doesn’t rely on any snapshot mechanism. It is also used if you are cloning an image into a different LINSTOR datastore.
LINSTOR_STORAGE_POOL
LINSTOR_STORAGE_POOL
attribute is used to select the LINSTOR storage pool your datastore
should use. If resource groups are used this attribute isn’t needed as the storage pool
can be select by the auto select filter options.
If LINSTOR_AUTO_PLACE
or LINSTOR_DEPLOYMENT_NODES
is used and LINSTOR_STORAGE_POOL
is not set, it will fallback to the DfltStorPool
in LINSTOR.
9.4.8. Configuring LINSTOR as a System Datastore
LINSTOR driver can also be used as a system datastore, configuration is pretty similar to normal datastores, with a few changes:
cat >system_ds.conf <<EOI NAME = linstor_system_datastore TM_MAD = linstor TYPE = SYSTEM_DS DISK_TYPE = BLOCK LINSTOR_RESOURCE_GROUP = "OneSysRscGrp" BRIDGE_LIST = "alice bob charlie" # node names EOI onedatastore create system_ds.conf
Also add the new sys datastore id to the COMPATIBLE_SYS_DS
to your image datastores (COMMA separated), otherwise the scheduler will ignore them.
If you want live migration with volatile disks you need to enable the --unsafe
option for KVM, see:
opennebula-doc
9.5. Live Migration
Live migration is supported even with the use of the SSH system datastore, as well as the nfs shared system datastore.
9.6. Free Space Reporting
Free space is calculated differently depending on whether resources are deployed automatically or on a per node basis.
For datastores which place per node, free space is reported based on the most restrictive storage pools from all nodes where resources are being deployed. For example, the capacity of the node with the smallest amount of total storage space is used to determine the total size of the datastore and the node with the least free space is used to determine the remaining space in the datastore.
For a datastore which uses automatic placement, size and remaining space are determined based on the aggregate storage pool used by the datastore as reported by LINSTOR.
10. LINSTOR Volumes in OpenStack
This chapter describes using LINSTOR to provision persistent, replicated, and high-performance block storage for OpenStack.
10.1. Introduction to OpenStack
OpenStack consists of a wide range of individual services; The service responsible for provisioning and managing block storage is called Cinder. Other openstack services such as the compute instance service Nova can request volumes from Cinder. Cinder will then make a volume accessible to the requesting service.
LINSTOR can integrate with Cinder using a volume driver. The volume driver translates calls to the Cinder API to LINSTOR commands. For example: requesting a volume from Cinder will create new resources in LINSTOR, Cinder Volume snapshots translate to snapshots in LINSTOR and so on.
10.2. Installing LINSTOR for OpenStack
An initial installation and configuration of DRBD and LINSTOR must be completed prior to using the OpenStack driver.
-
A detailed installation guide can be found here.
-
Initialize your cluster.
-
Learn how to use the LINSTOR client.
-
Add all storage nodes to the LINSTOR cluster.
At this point you should be able to list your storage cluster nodes using the LINSTOR client:
$ linstor node info
╭────────────────────────────────────────────────────────────────────────────╮
┊ Node ┊ NodeType ┊ Addresses ┊ State ┊
╞════════════════════════════════════════════════════════════════════════════╡
┊ cinder-01.openstack.test ┊ COMBINED ┊ 10.43.224.21:3366 (PLAIN) ┊ Online ┊
┊ cinder-02.openstack.test ┊ COMBINED ┊ 10.43.224.22:3366 (PLAIN) ┊ Online ┊
┊ storage-01.openstack.test ┊ SATELLITE ┊ 10.43.224.11:3366 (PLAIN) ┊ Online ┊
┊ storage-02.openstack.test ┊ SATELLITE ┊ 10.43.224.12:3366 (PLAIN) ┊ Online ┊
┊ storage-03.openstack.test ┊ SATELLITE ┊ 10.43.224.13:3366 (PLAIN) ┊ Online ┊
╰────────────────────────────────────────────────────────────────────────────╯
You should configure one or more storage pools per node. This guide assumes the
storage pool is named cinderpool
. LINSTOR should list the storage pool for each node, including the diskless storage
pool created by default.
$ linstor storage-pool list
╭─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
┊ StoragePool ┊ Node ┊ Driver ┊ PoolName ┊ FreeCapacity ┊ TotalCapacity ┊ CanSnapshots ┊ State ┊
╞═════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════╡
┊ DfltDisklessStorPool ┊ cinder-01.openstack.test ┊ DISKLESS ┊ ┊ ┊ ┊ False ┊ Ok ┊
┊ DfltDisklessStorPool ┊ cinder-02.openstack.test ┊ DISKLESS ┊ ┊ ┊ ┊ False ┊ Ok ┊
┊ DfltDisklessStorPool ┊ storage-01.openstack.test ┊ DISKLESS ┊ ┊ ┊ ┊ False ┊ Ok ┊
┊ DfltDisklessStorPool ┊ storage-02.openstack.test ┊ DISKLESS ┊ ┊ ┊ ┊ False ┊ Ok ┊
┊ DfltDisklessStorPool ┊ storage-03.openstack.test ┊ DISKLESS ┊ ┊ ┊ ┊ False ┊ Ok ┊
┊ cinderpool ┊ storage-01.openstack.test ┊ LVM_THIN ┊ ssds/cinderpool ┊ 100 GiB ┊ 100 GiB ┊ True ┊ Ok ┊
┊ cinderpool ┊ storage-02.openstack.test ┊ LVM_THIN ┊ ssds/cinderpool ┊ 100 GiB ┊ 100 GiB ┊ True ┊ Ok ┊
┊ cinderpool ┊ storage-03.openstack.test ┊ LVM_THIN ┊ ssds/cinderpool ┊ 100 GiB ┊ 100 GiB ┊ True ┊ Ok ┊
╰─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
10.2.1. Upgrading the LINSTOR Driver
If this is a fresh installation, skip this section and continue with Installing the LINSTOR Driver.
Upgrading From 1.x to 2.x
Driver version 2 dropped some static configuration options in favour of managing these options at runtime using volume types.
Option in cinder.conf |
Status | Replace with |
---|---|---|
|
removed |
Use the |
|
removed |
No replacement needed, the driver will create a diskless resource on the cinder host when required |
|
removed |
This setting had no effect. |
|
deprecated |
This setting is deprecated for removal in a future version. Use the |
|
deprecated |
Replaced by the more aptly named |
|
removed |
Creating nodes and storage pools was completely removed in Driver version 2. See Installing LINSTOR for OpenStack |
|
removed |
This setting served no purpose, it was removed without replacement. |
10.2.2. Installing the LINSTOR Driver
Starting with OpenStack Stein, the LINSTOR driver is part of the Cinder project. While the driver can be used as is, it might be missing features or fixes available in newer version. Due to OpenStacks update policy for stable versions, most improvements to the driver will not get back-ported to older stable releases.
LINBIT maintains a fork of the Cinder repository with all improvements to the LINSTOR driver backported to the supported stable versions. Currently, these are:
OpenStack Release | Included Version | LINBIT Version | LINBIT Branch |
---|---|---|---|
|
1.0.1 |
2.0.0 |
|
|
1.0.1 |
2.0.0 |
|
|
1.0.1 |
2.0.0 |
|
|
1.0.1 |
2.0.0 |
|
|
1.0.1 |
2.0.0 |
|
|
1.0.0 |
2.0.0 |
|
|
1.0.0 |
2.0.0 |
The exact steps to enable the LINSTOR Driver depend on your OpenStack distribution. In general, the python-linstor
package needs to be installed on all hosts running the Cinder volume service. The next section will cover the
installation process for common OpenStack distributions.
Installing on DevStack
DevStack is a great way to try out OpenStack in a lab environment. To use the most recent driver use the following DevStack configuration:
# This ensures the LINSTOR Driver has access to the 'python-linstor' package. # # This is needed even if using the included driver! USE_VENV=True ADDITIONAL_VENV_PACKAGES=python-linstor # This is required to select the LINBIT version of the driver CINDER_REPO=https://github.com/LINBIT/openstack-cinder.git # Replace linstor/stable/victoria with the reference matching your OpenStack release. CINDER_BRANCH=linstor/stable/victoria
Installing on Kolla
Kolla packages OpenStack components in containers. They can then be deployed, for example using Kolla Ansible You can take advantage of the available customisation options for kolla containers to set up the LINSTOR driver.
To ensure that the required python-linstor
package is installed, use the following override file:
{% extends parent_template %}
# Cinder
{% set cinder_base_pip_packages_append = ['python-linstor'] %}
To install the LINBIT version of the driver, update your kolla-build.conf
[cinder-base] type = git location = https://github.com/LINBIT/openstack-cinder.git # Replace linstor/stable/victoria with the reference matching your OpenStack release. reference = linstor/stable/victoria
To rebuild the Cinder containers, run:
# A private registry used to store the kolla container images
REGISTRY=deployment-registry.example.com
# The image namespace in the registry
NAMESPACE=kolla
# The tag to apply to all images. Use the release name for compatibility with kolla-ansible
TAG=victoria
kolla-build -t source --template-override template-override.j2 cinder --registry $REGISTRY --namespace $NAMESPACE --tag $TAG
Kolla Ansible Deployment
When deploying OpenStack using Kolla Ansible, you need to verify that:
-
the custom Cinder images, created in the section above, are used deployment of Cinder services is enabled.
# use "source" images
kolla_install_type: source
# use the same registry as for running kolla-build above
docker_registry: deployment-registry.example.com
# use the same namespace as for running kolla-build above
docker_namespace: kolla
# deploy cinder block storage service
enable_cinder: "yes"
# disable verification of cinder back ends, kolla-ansible only supports a small subset of available back ends for this
skip_cinder_backend_check: True
# add the LINSTOR back end to the enabled back ends. For back end configuration see below
cinder_enabled_backends:
- name: linstor-drbd
You can place the LINSTOR driver configuration in one of the override directories for kolla-ansible. For more details on the available configuration options, see the section below.
[linstor-drbd] volume_backend_name = linstor-drbd volume_driver = cinder.volume.drivers.linstordrv.LinstorDrbdDriver linstor_uris = linstor://cinder-01.openstack.test,linstor://cinder-02.openstack.test
OpenStack Ansible Deployment
OpenStack Ansible provides Ansible playbooks to configure and deploy of OpenStack environments. It allows for fine-grained customization of the deployment, letting you set up the LINSTOR driver directly.
cinder_git_repo: https://github.com/LINBIT/openstack-cinder.git cinder_git_install_branch: linstor/stable/victoria cinder_user_pip_packages: - python-linstor cinder_backends: (1) linstor-drbd: volume_backend_name: linstor-drbd volume_driver: cinder.volume.drivers.linstordrv.LinstorDrbdDriver linstor_uris: linstor://cinder-01.openstack.test,linstor://cinder-02.openstack.test
1 | A detailed description of the available back end parameters can be found in the section below. |
Generic Cinder Deployment
For other forms of OpenStack deployments, this guide can only provide non-specific hints.
To update the LINSTOR driver version, find your Cinder installation. Some likely paths are:
/usr/lib/python*/dist-packages/cinder/ /usr/lib/python*/site-packages/cinder/
The LINSTOR driver consists of a single file called linstordrv.py
, located in the Cinder directory:
$CINDER_PATH/volume/drivers/linstordrv.py
To update the driver, replace the file with one from the LINBIT repository
RELEASE=linstor/stable/victoria curl -fL "https://raw.githubusercontent.com/LINBIT/openstack-cinder/$RELEASE/cinder/volume/drivers/linstordrv.py" > $CINDER_PATH/volume/drivers/linstordrv.py
You might also need to remove the Python cache for the update to be registered:
rm -rf $CINDER_PATH/volume/drivers/__pycache__
10.3. Configuring a LINSTOR Back End for Cinder
To use the LINSTOR driver, configure the Cinder volume service. This is done by editing the Cinder configuration file and then restarting the Cinder Volume service.
Most of the time, the Cinder configuration file is located at /etc/cinder/cinder.conf
. Some deployment options allow
manipulating this file in advance. See the section above for specifics.
To configure a new volume back end using LINSTOR, add the following section to cinder.conf
[linstor-drbd] volume_backend_name = linstor-drbd (1) volume_driver = cinder.volume.drivers.linstordrv.LinstorDrbdDriver (2) linstor_uris = linstor://cinder-01.openstack.test,linstor://cinder-02.openstack.test (3) linstor_trusted_ca = /path/to/trusted/ca.cert (4) linstor_client_key = /path/to/client.key (5) linstor_client_cert = /path/to/client.cert (5) # Deprecated or removed in 2.0.0 linstor_default_storage_pool_name = cinderpool (6) linstor_autoplace_count = 2 (7) linstor_controller_diskless = true (8) # non-linstor-specific options ... (9)
The parameters described here are based on the latest release provided by LINBIT. The driver included in OpenStack might not support all of these parameters. Consult the OpenStack driver documentation to learn more. |
1 | The name of the volume back end. Needs to be unique in the Cinder configuration. The whole
section should share the same name. This name is referenced again in cinder.conf in the
enabled_backends setting and when creating a new volume type. |
||
2 | The version of the LINSTOR driver to use. There are two options:
|
||
3 | The URL(s) of the LINSTOR Controller(s). Multiple Controllers can be specified to make use of Linstor High Availability. If not set, defaults to linstor://localhost .
|
||
4 | If HTTPS is enabled the referenced certificate is used to verify the LINSTOR Controller authenticity. | ||
5 | If HTTPS is enabled the referenced key and certificate will be presented to the LINSTOR Controller for authentication. | ||
6 | Deprecated in 2.0.0, use volume types instead. The storage pools to use when placing resources. Applies to all diskfull resources created. Defaults to DfltStorPool . |
||
7 | Removed in 2.0.0, use volume types instead. The number of replicas to create for the given volume. A value of 0 will create a replica on all nodes. Defaults to 0 . |
||
8 | Removed in 2.0.0, volumes are created on demand by the driver. If set to true, ensures that at least one (diskless) replica is deployed on the Cinder Controller host. This is useful for ISCSI transports. Defaults to true . |
||
9 | You can specify more generic Cinder options here, for example target_helper = tgtadm for the ISCSI connector. |
You can also configure multiple LINSTOR back ends, choosing a different name and configuration options for each. |
After configuring the LINSTOR back end, it should also be enabled. Add it to the list of enabled back ends in cinder.conf
,
and optionally set is as the default back end:
[DEFAULT] ... default_volume_type = linstor-drbd-volume enabled_backends = lvm,linstor-drbd ...
As a last step, if you changed the Cinder configuration or updated the driver itself, you need to restart the Cinder service(s). Please check the documentation for your OpenStack Distribution on how to restart services.
10.3.1. Choosing a Transport Protocol
The Transport Protocol in Cinder is how clients (for example nova-compute) access the actual volumes. With LINSTOR, you can choose between two different drivers that use different transports.
-
cinder.volume.drivers.linstordrv.LinstorDrbdDriver
, which uses DRBD as transport -
cinder.volume.drivers.linstordrv.LinstorIscsiDriver
, which uses ISCSI as transport
Using DRBD as the Transport Protocol
The LinstorDrbdDriver
works by ensuring a replica of the volume is available locally on the node where
a client (that is, nova-compute) issued a request. This only works if all compute nodes are also running
LINSTOR Satellites that are part of the same LINSTOR cluster.
The advantages of this option are:
-
Once set up, the Cinder host is no longer involved in the data path. All read and write to the volume are handled by the local DRBD module, which will handle replication across its configured peers.
-
Since the Cinder host is not involved in the data path, any disruptions to the Cinder service do not affect volumes that are already attached.
Known limitations:
-
Not all hosts and hypervisors support using DRBD volumes. This restricts deployment to Linux hosts and
kvm
hypervisors. -
Resizing of attached and in-use volumes does not fully work. While the resize itself is successful, the compute service will not propagate it to the VM until after a restart.
-
Multi-attach (attaching the same volume on multiple VMs) is not supported.
-
Encrypted volumes only work if udev rules for DRBD devices are in place.
udev
rules are either part of thedrbd-utils
package or have their owndrbd-udev
package.
Using iSCSI as the Transport Protocol
The default way to export Cinder volumes is through iSCSI. This has the advantage of maximum compatibility as iSCSI can be used with every hypervisor, be it VMWare, Xen, HyperV, or KVM.
The drawback is that all data has to be sent to a Cinder node, to be processed by an (userspace) iSCSI daemon; that means that the data needs to pass the kernel/userspace border, and these transitions will cost some performance.
Another drawback is the introduction of a single point of failure. If a Cinder node running the iSCSI daemon crashes, other nodes lose access to their volumes. There are ways to configure Cinder for automatic fail-over to mitigate this, but it requires considerable effort.
In driver versions prior to 2.0.0, the Cinder host needs access to a local replica of every volume. This can be
achieved by either setting linstor_controller_diskless=True or using linstor_autoplace_count=0 . Newer driver
versions will create such a volume on demand.
|
10.3.2. Verifying the Status of LINSTOR Back Ends
To verify that all back ends are up and running, you can use the OpenStack command line client:
$ openstack volume service list
+------------------+----------------------------------------+------+---------+-------+----------------------------+
| Binary | Host | Zone | Status | State | Updated At |
+------------------+----------------------------------------+------+---------+-------+----------------------------+
| cinder-scheduler | cinder-01.openstack.test | nova | enabled | up | 2021-03-10T12:24:37.000000 |
| cinder-volume | cinder-01.openstack.test@linstor-drbd | nova | enabled | up | 2021-03-10T12:24:34.000000 |
| cinder-volume | cinder-01.openstack.test@linstor-iscsi | nova | enabled | up | 2021-03-10T12:24:35.000000 |
+------------------+----------------------------------------+------+---------+-------+----------------------------+
If you have the Horizon GUI deployed, check Admin > System Information > Block Storage Service
instead.
In the above example all configured services are enabled
and up
. If there are any issues, please check
the logs of the Cinder Volume service.
10.4. Creating a New Volume Type for LINSTOR
Before creating volumes using Cinder, you have to create a volume type. This can be done using the command line:
# Create a volume using the default back end
$ openstack volume type create default
+-------------+--------------------------------------+
| Field | Value |
+-------------+--------------------------------------+
| description | None |
| id | 58365ffb-959a-4d91-8821-5d72e5c39c26 |
| is_public | True |
| name | default |
+-------------+--------------------------------------+
# Create a volume using a specific back end
$ openstack volume type create --property volume_backend_name=linstor-drbd linstor-drbd-volume
+-------------+--------------------------------------+
| Field | Value |
+-------------+--------------------------------------+
| description | None |
| id | 08562ea8-e90b-4f95-87c8-821ac64630a5 |
| is_public | True |
| name | linstor-drbd-volume |
| properties | volume_backend_name='linstor-drbd' |
+-------------+--------------------------------------+
Alternatively, you can create volume types using the Horizon GUI. Navigate to Admin > Volume > Volume Types
and click
“Create Volume Type”. You can assign it a back end by adding the volume_backend_name
as “Extra Specs” to it.
10.4.1. Advanced Configuration of Volume Types
Each volume type can be customized by adding properties or “Extra Specs” as they are called in the Horizon GUI.
To add a property to a volume type on the command line use:
openstack volume type set linstor_drbd_b --property linstor:redundancy=5
Alternatively, you can set the property using the GUI by navigating tp Admin > Volume > Volume Types
. In the Actions
column, open the dropdown menu and click the View Extra Specs
button. This opens a dialog you can use to create, edit
and delete properties.
Available Volume Type Properties
- linstor:diskless_on_remaining
-
Create diskless replicas on non-selected nodes after auto-placing.
- linstor:do_not_place_with_regex
-
Do not place the resource on a node which has a resource with a name matching the regex.
- linstor:layer_list
-
Comma-separated list of layers to apply for resources. If empty, defaults to DRBD,Storage.
- linstor:provider_list
-
Comma-separated list of providers to use. If empty, LINSTOR will automatically choose a suitable provider.
- linstor:redundancy
-
Number of replicas to create. Defaults to two.
- linstor:replicas_on_different
-
A comma-separated list of key or key=value items used as autoplacement selection labels when autoplace is used to determine where to provision storage.
- linstor:replicas_on_same
-
A comma-separated list of key or key=value items used as autoplacement selection labels when autoplace is used to determine where to provision storage.
- linstor:storage_pool
-
Comma-separated list of storage pools to use when auto-placing.
- linstor:property:<key>
-
If a <key> is prefixed by
linstor:property:
, it is interpreted as a LINSTOR property. The property gets set on the Resource Group created for the volume type.OpenStack does not allow for
/
in property names. If a LINSTOR property name contains a/
replace it with a:
.For example: To change the quorum policy,
DrbdOptions/auto-quorum
needs to be set. This can be done by setting thelinstor:property:DrbdOptions:auto-quorum
property in OpenStack.
10.5. Using Volumes
Once you have a volume type configured, you can start using it to provision new volumes.
For example, to create a simple 1Gb volume on the command line you can use:
openstack volume create --type linstor-drbd-volume --size 1 \
--availability-zone nova linstor-test-vol
openstack volume list
If you set default_volume_type = linstor-drbd-volume in your /etc/cinder/cinder.conf ,
you may omit the --type linstor-drbd-volume from the openstack volume create … command above.
|
10.6. Troubleshooting
This section describes what to do in case you encounter problems with using LINSTOR volumes and snapshots.
10.6.1. Checking for Error Messages in Horizon
Every volume and snapshot has a Messages tab in the Horizon dashboard. In case of errors, you can use the list of messages as a starting point for further investigation. Some common messages in case of errors:
create volume from backend storage:Driver failed to create the volume.
This message shows that there was an error creating a new volume. Check the Cinder Volume service logs for more details.
schedule allocate volume:Could not find any available weighted backend.
If this is the only error message, this means that the Cinder Scheduler could not find a volume back end suitable for creating the volume. This is most likely because:
-
The volume back end is offline. See Verifying the Status of LINSTOR Back Ends.
-
The volume back end does not have enough free capacity to fulfil the request. Check the output of
cinder get-pools --detail
andlinstor storage-pool list
to verify that the requested capacity is available.
10.6.2. Checking the Cinder Volume Service
The LINSTOR driver is called as part of the Cinder Volume service.
Distribution | Log location or command |
---|---|
DevStack |
|
10.6.3. Checking the Compute Service Logs
Some issues will not be logged in the Cinder Service but in the actual consumer of the volumes, most likely the compute service (Nova). As with the volume service, the exact host and location to check depends on your OpenStack distribution:
Distribution | Log location or command |
---|---|
DevStack |
|
11. LINSTOR Volumes in Docker
This chapter describes LINSTOR volumes in Docker as managed by the LINSTOR Docker Volume Plugin.
11.1. Introduction to Docker
Docker is a platform for developing, shipping, and running applications in the form of Linux containers. For stateful applications that require data persistence, Docker supports the use of persistent volumes and volume_drivers.
The LINSTOR Docker Volume Plugin is a volume driver that provisions persistent volumes from a LINSTOR cluster for Docker containers.
11.2. Installing the LINSTOR Plug-in for Docker
To install the linstor-docker-volume
plug-in provided by LINBIT, you’ll
need to have a working LINSTOR cluster. After that the plug-in can be installed from the public docker hub.
# docker plugin install linbit/linstor-docker-volume --grant-all-permissions
The --grant-all-permissions flag will automatically grant all
permissions needed to successfully install the plug-in. If you’d like to
manually accept these, omit the flag from the command above.
|
The implicit :latest
tag is the latest amd64
version. We currently also build for arm64
with the
according tag. Installing the arm64
plugin looks like this:
# docker plugin install linbit/linstor-docker-volume:arm64 --grant-all-permissions
11.3. Configuring the LINSTOR Plug-in for Docker
As the plug-in has to communicate to the LINSTOR Controller software using the LINSTOR Python library, we must tell the plug-in where to find the LINSTOR controller node in its configuration file:
# cat /etc/linstor/docker-volume.conf [global] controllers = linstor://hostnameofcontroller
A more extensive example could look like this:
# cat /etc/linstor/docker-volume.conf [global] storagepool = thin-lvm fs = ext4 fsopts = -E discard size = 100MB replicas = 2
11.4. Using the LINSTOR Plug-in for Docker
The following are some examples of how you might use the LINSTOR Docker Volume Plug-in. In the following we expect a cluster consisting of three nodes (alpha, bravo, and charlie).
11.4.1. Typical Docker Pattern
On node alpha:
$ docker volume create -d linbit/linstor-docker-volume \ --opt fs=xfs --opt size=200 lsvol $ docker run -it --rm --name=cont \ -v lsvol:/data --volume-driver=linbit/linstor-docker-volume busybox sh $ root@cont: echo "foo" > /data/test.txt $ root@cont: exit
On node bravo:
$ docker run -it --rm --name=cont \ -v lsvol:/data --volume-driver=linbit/linstor-docker-volume busybox sh $ root@cont: cat /data/test.txt foo $ root@cont: exit $ docker volume rm lsvol
11.4.2. One Diskful Assignment by Name, Two Nodes Diskless
$ docker volume create -d linbit/linstor-docker-volume --opt nodes=bravo lsvol
11.4.3. One Diskful Assignment, No Matter Where, Two Nodes Diskless
$ docker volume create -d linbit/linstor-docker-volume --opt replicas=1 lsvol
11.4.4. Two Diskful Assignments by Name, and One Diskless
$ docker volume create -d linbit/linstor-docker-volume --opt nodes=alpha,bravo lsvol
11.4.5. Two Diskful Assignments, No Matter Where, One Node Diskless
$ docker volume create -d linbit/linstor-docker-volume --opt replicas=2 lsvol
11.4.6. Using LINSTOR Volumes with Services from Docker Swarm Manager Node
$ docker service create \ --mount type=volume,src=lsvol,dst=/data,volume-driver=linbit/linstor-docker-volume \ --name swarmsrvc busybox sh -c "while true; do sleep 1000s; done"
Docker services do not accept the -v or --volume syntax, you
must use the --mount syntax. Docker run will accept either syntax.
|
12. LINSTOR Gateway for Highly Available NFS/iSCSI/NVMe-oF Storage
LINSTOR Gateway manages highly available NVMe-oF targets, iSCSI targets, and NFS exports by leveraging both LINSTOR and DRBD Reactor.
12.1. LINSTOR Gateway Requirements
Before you can use LINSTOR Gateway, you will need to have an initialized LINSTOR cluster, with DRBD Reactor, as well as NVMe-oF, NFS, iSCSI utilities installed and configured. The following sections detail how to meet these requirements.
12.1.1. LINSTOR Cluster
The LINSTOR cluster needs to be set up as a prerequisite to using LINSTOR Gateway. For more detail regarding LINSTOR’s configuration options, please refer to the LINSTOR User’s Guide.
For NVMe-oF, iSCSI, and NFS, a LINSTOR storage-pool
, resource-group
, and volume-group
for LINSTOR Gateway need to be
created before use. The following section provides example commands for setting up the prerequisites in a three-node
LINSTOR cluster.
Create a LVM backed storage-pool on each node using the physical device /dev/sdb
:
# linstor physical-storage create-device-pool --pool-name lvpool LVM LINSTOR1 /dev/sdb --storage-pool lvmpool # linstor physical-storage create-device-pool --pool-name lvpool LVM LINSTOR2 /dev/sdb --storage-pool lvmpool # linstor physical-storage create-device-pool --pool-name lvpool LVM LINSTOR3 /dev/sdb --storage-pool lvmpool
Create resource-groups and volume-groups backed by the storage-pool created in the previous command:
# linstor resource-group create iscsi_group --storage-pool lvmpool --place-count 2 # linstor resource-group create nfs_group --storage-pool lvmpool --place-count 3 # linstor resource-group create nvme_group --storage-pool lvm --place-count 2
# linstor volume-group create iscsi_group # linstor volume-group create nfs_group # linstor volume-group create nvmeof_group
LINSTOR Gateway requires modification of the LINSTOR Satellite’s configuration on each Satellite node. Edit or create the following file using your preferred text editor:
# vim /etc/linstor/linstor_satellite.toml
Add the following content to the Satellite configuration:
[files] allowExtFiles = [ "/etc/systemd/system", "/etc/systemd/system/linstor-satellite.service.d", "/etc/drbd-reactor.d" ]
Save the changes to the Satellite configuration and restart the satellite service on all nodes to load the changes.
# systemctl restart linstor-satellite
12.1.2. DRBD Reactor
DRBD Reactor is a daemon that will orchestrate the iSCSI, NFS or NVMe-oF resources in our cluster. It must be installed and the service must be enabled on all nodes in the cluster.
DRBD Reactor’s main function could be summarized as such: each DRBD Reactor daemon tries to take over DRBD Reactor managed services. The daemon that wins the race prevents other nodes from activating the services until the original winner is no longer able to. When that happens, a new winner will take over DRBD Reactor managed services, therefore achieving high-availability.
For details regarding DRBD Reactor’s installation and configuration options, refer to the DRBD Reactor GitHub page.
Start and enable the DRBD Reactor service on all nodes:
# systemctl enable --now drbd-reactor
In addition to this, DRBD Reactor needs to be configured to automatically reload when its configuration changes. Run this snippet on all nodes, as described in the DRBD Reactor README:
# cp examples/drbd-reactor-reload.{path,service} /etc/systemd/system/ # systemctl enable --now drbd-reactor-reload.path
DRBD Reactor uses Pacemaker’s resource agents when integrated with LINSTOR Gateway. You also need to install resource
agents on all nodes in the cluster. This package is named resource-agents
in both RPM and DEB based distributions:
# dnf -y install resource-agents
12.1.3. NVME-oF, iSCSI, and NFS Utilities
To configure NVMe-oF targets for LINSTOR Gateway, you will need to install the NVMe-of command line interface on all nodes.
The nvmetcli
package can be installed on RPM based systems using the following command:
# dnf -y install nvmetcli
LINSTOR Gateway requires the LIO iSCSI implementation be installed on all nodes.
The targetcli
package can be installed on RPM based systems using the following command:
# dnf -y install targetcli
For NFS support in LINSTOR Gateway, nfs-server utilities need to be installed on each node.
The nfs-utils
package can be installed on RPM based systems using the following command:
# dnf -y install nfs-utils
The NFS server should not be enabled in systemd since that will conflict with DRBD Reactors ability to manage the service. Disable the nfs-server service and check that it has been disabled using the following commands:
# systemctl disable nfs-server --now # systemctl status nfs-server
Ensure that the output of the command above lists the service as inactive
and disabled
:
● nfs-server.service - NFS server and services Loaded: loaded (/usr/lib/systemd/system/nfs-server.service; disabled; ..snip..) Active: inactive (dead)
12.2. Verifying Requirements are Satisfied
The last thing we can do before starting to use LINSTOR Gateway is check that we’ve satisfied the prerequisites outlined in the previous sections.
12.2.1. Verifying Components are Installed
Let’s check that all the required components are present. This guide assumes you already installed and configured a LINSTOR cluster complete with storage-pools, resource-groups, and volume-groups before using linstor-gateway.
In addition to the initialized LINSTOR cluster, the following tools need to be present on all nodes:
-
linstor-client
-
drbd-reactor
-
nvmetcli
-
targetcli
-
nfs-utils (RPM) or nfs-common (DEB)
-
nfs-server (RPM) or nfs-kernel-server (DEB)
-
resource-agents
LINSTOR Gateway provides a utility to check that the prerequisite tools are present:
# linstor-gateway check-health
This command should print something similar to the output below if you installed all of the required components. If an error is reported, you must resolve the error before proceeding.
[✓] LINSTOR [✓] drbd-reactor [✓] Resource Agents [✓] iSCSI [✓] NVMe-oF [✓] NFS
12.2.2. Verifying LINSTOR Cluster Initialization
Verify that the LINSTOR cluster is initialized properly by comparing your outputs are similar to the outputs in the commands below.
Ensure all your LINSTOR nodes are listed as a Satellite or Combined type, and that you have 3 (or more) to support quorum:
# linstor node list ╭────────────────────────────────────────────────────────────╮ ┊ Node ┊ NodeType ┊ Addresses ┊ State ┊ ╞════════════════════════════════════════════════════════════╡ ┊ LINSTOR1 ┊ COMBINED ┊ 172.16.16.111:3366 (PLAIN) ┊ Online ┊ ┊ LINSTOR2 ┊ SATELLITE ┊ 172.16.16.112:3366 (PLAIN) ┊ Online ┊ ┊ LINSTOR3 ┊ SATELLITE ┊ 172.16.16.113:3366 (PLAIN) ┊ Online ┊ ╰────────────────────────────────────────────────────────────╯
Check that LINSTOR’s storage-pool list includes an LVM or ZFS backed storage-pool:
# linstor storage-pool list ╭─────────────────────────────────────────────────────────..snip..─────────╮ ┊ StoragePool ┊ Node ┊ Driver ┊ PoolName ┊ ..snip.. ┊ State ┊ ╞═════════════════════════════════════════════════════════..snip..═════════╡ ┊ DfltDisklessStorPool ┊ LINSTOR1 ┊ DISKLESS ┊ ┊ ..snip.. ┊ Ok ┊ ┊ DfltDisklessStorPool ┊ LINSTOR2 ┊ DISKLESS ┊ ┊ ..snip.. ┊ Ok ┊ ┊ DfltDisklessStorPool ┊ LINSTOR3 ┊ DISKLESS ┊ ┊ ..snip.. ┊ Ok ┊ ┊ lvmpool ┊ LINSTOR1 ┊ LVM ┊ lvpool ┊ ..snip.. ┊ Ok ┊ ┊ lvmpool ┊ LINSTOR2 ┊ LVM ┊ lvpool ┊ ..snip.. ┊ Ok ┊ ┊ lvmpool ┊ LINSTOR3 ┊ LVM ┊ lvpool ┊ ..snip.. ┊ Ok ┊ ╰─────────────────────────────────────────────────────────..snip..─────────╯
Check that you’ve created at least one LINSTOR resource-group that uses your storage-pool. Also verify that each resource-group has a corresponding volume-group:
# linstor resource-group list ╭────────────────────────────────────────────────────────────────╮ ┊ ResourceGroup ┊ SelectFilter ┊ VlmNrs ┊ Description ┊ ╞════════════════════════════════════════════════════════════════╡ ┊ DfltRscGrp ┊ PlaceCount: 2 ┊ ┊ ┊ ╞┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄╡ ┊ iscsi_group ┊ PlaceCount: 2 ┊ 0 ┊ ┊ ┊ ┊ StoragePool(s): lvmpool ┊ ┊ ┊ ╞┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄╡ ┊ nvmeof_group ┊ PlaceCount: 2 ┊ 0 ┊ ┊ ┊ ┊ StoragePool(s): lvmpool ┊ ┊ ┊ ╞┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄╡ ┊ nfs_group ┊ PlaceCount: 3 ┊ 0 ┊ ┊ ┊ ┊ StoragePool(s): lvmpool ┊ ┊ ┊ ╰────────────────────────────────────────────────────────────────╯ # linstor volume-group list iscsi_group ╭──────────────────╮ ┊ VolumeNr ┊ Flags ┊ ╞══════════════════╡ ┊ 0 ┊ ┊ ╰──────────────────╯ # linstor volume-group list nfs_group ╭──────────────────╮ ┊ VolumeNr ┊ Flags ┊ ╞══════════════════╡ ┊ 0 ┊ ┊ ╰──────────────────╯ # linstor volume-group list nvmeof_group ╭──────────────────╮ ┊ VolumeNr ┊ Flags ┊ ╞══════════════════╡ ┊ 0 ┊ ┊ ╰──────────────────╯
12.3. Creating iSCSI Targets
Once the preparations are complete, you can start creating iSCSI luns. The linstor-gateway
command line utility will
be used to manage all iSCSI related actions.
Use linstor-gateway iscsi help for detailed information regarding the iscsi subcommand.
|
The following command will create a new DRBD resource in the LINSTOR cluster with the specified name and resource-group. This command also creates the DRBD Reactor configuration files to enable high availability of the iSCSI target.
# linstor-gateway iscsi create iqn.2019-08.com.linbit:example 192.168.122.181/24 1G \ --username=foo --password=bar --resource-group=iscsi_group
After running the command above, you will have a 1GiB iSCSI target with CHAP authentication enabled using the username and
password provided. It will be discoverable on the IP address provided in the command. The target will be backed by a
DRBD device managed by LINSTOR. The DRBD resource was created by LINSTOR in the iscsi_group
resource-group. The DRBD
Reactor configuration files created by the above command can be found in /etc/drbd-reactor.d/
.
You can list LINSTOR Gateway created iSCSI resources using the linstor-gateway iscsi list
command:
# linstor-gateway iscsi list +--------------------------------+--------------------+---------------+-----+---------------+ | IQN | Service IP | Service state | LUN | LINSTOR state | +--------------------------------+--------------------+---------------+-----+---------------+ | iqn.2019-08.com.linbit:example | 192.168.122.181/24 | Started | 1 | OK | +--------------------------------+--------------------+---------------+-----+---------------+
You can check the DRBD Reactor status using the drbd-reactorctl status command.
|
12.4. Deleting iSCSI Targets
The following command will delete the iSCSI target from DRBD Reactor as well as the LINSTOR cluster:
# linstor-gateway delete -i iqn.2021-04.com.linbit:lun4 -l 4
12.5. Creating NFS Exports
Before creating a NFS export you need to tell LINSTOR which filesystem the DRBD resource should be formatted with.
This is done by setting the FileSystem/Type
property on the resource-group created for NFS exports. Use
the following LINSTOR command to do so:
# linstor resource-group set-property nfs_group FileSystem/Type ext4
You only need to set this once per resource-group, and only on the resource-group created specifically for LINSTOR Gateway’s NFS exports. |
Finally, the following command will create a HA NFS export in the cluster. This single command will create a new resource within the LINSTOR cluster using the specified name and resource-group. This command also creates the DRBD Reactor configuration files to enable high availability of the NFS export.
# linstor-gateway nfs create nfstest 172.16.16.102/32 1G \ --allowed-ips=172.16.16.0/24 --resource-group=nfs_group
After running the command above, you will have a 1GiB NFS export with the specified allowed-ips
able to mount the export
using the IP address specified as the --service-ip
. The exports will be backed by a DRBD device managed by LINSTOR.
The DRBD resource was created by LINSTOR in the nfs_group
resource-group. The DRBD Reactor configuration files created
by the above command can be found in /etc/drbd-reactor.d/
.
You can list LINSTOR Gateway created NFS resources using the linstor-gateway nfs list
command:
# LINSTOR-gateway nfs list +----------+------------------+---------------+------------------------------+---------------+ | Resource | Service IP | Service state | NFS export | LINSTOR state | +----------+------------------+---------------+------------------------------+---------------+ | nfstest | 172.16.16.102/32 | Started | /srv/gateway-exports/nfstest | OK | +----------+------------------+---------------+------------------------------+---------------+
You can check the DRBD Reactor status using the drbd-reactorctl status command.
|
12.6. Deleting NFS Exports
The following command will delete the NFS export from DRBD Reactor as well as the LINSTOR cluster:
# linstor-gateway nfs delete -r nfstest
12.7. Creating NVMe-oF Targets
The linstor-gateway
command line utility will be used to manage all NVMe-oF target related actions.
Use linstor-gateway nvme help for detailed information regarding the nvme subcommand.
|
The following command will create a new DRBD resource in the LINSTOR cluster with the specified name and resource group. This command also creates the DRBD Reactor configuration files to enable high availability of the NVMe-oF target.
# linstor-gateway nvme create linbit:nvme:vol0 192.168.221.69/24 2G
After running the command above, you will have a highly available 2GiB NVMe-oF target created in your cluster that is discoverable
on the IP address used in the command. The target will be backed by a DRBD device managed by LINSTOR. The DRBD resource
was created by LINSTOR in the nvmeof_group
resource group. The DRBD Reactor configuration files created by the above
command can be found in /etc/drbd-reactor.d/
.
You can list the NVMe-oF resources that you created by using LINSTOR Gateway by entering the linstor-gateway nvme list
command:
# linstor-gateway nvme list +------------------+-------------------+---------------+-----------+---------------+ | NQN | Service IP | Service state | Namespace | LINSTOR state | +------------------+-------------------+---------------+-----------+---------------+ | linbit:nvme:vol0 | 192.168.221.69/24 | Started | 1 | OK | +------------------+-------------------+---------------+-----------+---------------+
You can check the DRBD Reactor status using the drbd-reactorctl status command.
|
13. LINSTOR Exos Integration
The Exos storage manager from Seagate could be configured as one large block device managed by LINSTOR like a local drive, but this would prevent concurrent sharing of LINSTOR resources between multiple servers out of the same pool.
LINSTOR integration with Exos enables multiple server nodes to allocate and connect to LINSTOR resources serviced by the same Exos pool. Therefore all of the Exos storage management features such as SSD/HDD tiering, SSD caching, snapshots, and thin provisioning are available for LINSTOR resources and Kubernetes Storage Classes.
After configuration, LINSTOR will dynamically map Resource replicas as LUNs presented to server nodes through one of the two Exos controllers.
Since the Exos controllers are managed by a secure network API, LINSTOR must be configured with proper networking and username/password combination. The diagram below is showing the relationship between LINSTOR cluster and Exos Enclosures.

Multi-host setup allows up to eight LINSTOR nodes to be directly connected with 48Gbit SAS links for low latency and high throughput. |
Load balancing and server failover are managed & enabled by LINSTOR while volume creation is handled by the Exos hardware RAID engine.
The Exos storage provider in LINSTOR offers native integration with Exos’ REST-API.
This section will describe how to enable Exos integration and configure LINSTOR to manage storage backed by an Exos enclosure.
Exos storage systems offer a feature rich set of configuration options to match any enterprise storage demand. To maximize ease of use, this guide is based on the following defaults and assumptions:
-
Dual Controllers – Exos systems controllers are Active/Active with automatic failover. Both controllers IP address must be configured also in the LINSTOR properties for full support.
-
Dual Exos Pools – Optimal performance is achieved when data from pool A is accessed through Controller A. If a node is connected to both Controller A and B of same controller, LINSTOR will configure Linux multipath which will detect best route.
-
Exos Pool Serial Numbers – When a Exos pool is created, it receives a unique serial number. Each one has to be configured as a backing storage in LINSTOR to create a link between Exos enclosure & LINSTOR. With that information, LINSTOR can understand if you are referring to Exos Pool A or Pool B.
-
Creating Exos Pools – The administrator is required to create Exos Pools A and B prior to configuring LINSTOR. Exos features such as thin provisioning, auto tiering, and snapshot options are selected at this time.
-
Replicas Within Enclosures – Exos system have redundant controllers, power supplies and communication paths to the drives. Some administrators may require that resource replicas are not stored in the same enclosure. In this case the administrator must create multiple LINSTOR Pools configured with only one Exos pool member from each enclosure.
13.1. Exos Properties as a LINSTOR Storage Provider
LINSTOR’s native integration with Exos is configured by setting a few properties on the LINSTOR Controller and creating the appropriate LINSTOR objects specific to your Exos enclosures, as described in the sections below.
The information in the table below is needed from your Exos enclosures. This information will be used to populate the appropriate LINSTOR Controller properties and LINSTOR objects in the sub-sections that follow.
Exos Information | Description | Placeholder in Command Examples |
---|---|---|
Exos Enclosure Name |
Uniquely selected by the Admin for a given Exos enclosure |
|
Controller Hostname |
The DNS resolvable hostname for one of the Controllers |
|
Controller IP |
IP address of controller |
|
REST-API Username |
Username for REST-API of all Exos controllers under the given enclosure |
|
REST-API Password |
Password for REST-API of all Exos controllers under the given enclosure |
|
Exos Pool Serial Number |
The serial number of an Exos pool to become a member of a LINSTOR Pool |
|
13.2. Configuring a LINSTOR and Exos Integration
Configuring a topology of LINSTOR server nodes and multiple Exos Storage systems is described by these steps:
-
Setting global or unique Exos Controller usernames and passwords.
-
Defining Exos enclosures and Controller network identities.
-
Creating node to enclosure to pool mapping matching physical SAS cabling.
13.2.1. Setting Exos Usernames and Passwords
Usernames and passwords can be unique for each Exos enclosure or be common for all enclosures depending on how the system administrator has deployed the Exos systems. The default Exos username and password will be used if not set for a given Exos controller.
The defaults are set as follows:
# linstor exos set-defaults --username <exos_rest_name> # linstor exos set-defaults --password <exos_rest_pass>
Unique usernames and passwords For Exos controllers are set by:
# linstor controller set-property StorDriver/Exos/<exos_encl_name>/username <exos_rest_name> # linstor controller set-property StorDriver/Exos/<exos_encl_name>/Password <exos_rest_pass>
Passwords entered in this fashion will
show up as plain text when using get-defaults .
|
With the above command, LINSTOR will store your password in plain text
in the LINSTOR properties and visible by a simple
linstor controller list-properties
command. You can hide it under
an environment variable, and use the UsernameEnv
and/or PasswordEnv
properties. This tells LINSTOR to look in environment variable for the
actual username/password, as shown in the following example:
LINSTOR will not modify the environment variables, only read from them. Storage admin has to verify that the environment variables are correctly set. |
# echo $EXOS_PW mySecretPassword # linstor controller set-property \ StorDriver/Exos/<exos_encl_name>/PasswordEnv EXOS_PW
If both property-versions (i.e. Password
and PasswordEnv
) are set,
the non-environment version is preferred.
If the satellite is started before the environment variable is set, the satellite needs to be restarted to see the new environment variable. |
13.2.2. Defining Exos Enclosures and Controller Identities
Registering an Exos enclosure in LINSTOR can be done with the create
command:
# linstor exos create <exos_encl_name> <exos_ctrl_a_ip> [<exos_ctrl_b_ip>]
If no special --username
or --password
is given, the above mentioned
defaults are used.
The Controller’s DNS name and IP address may be used interchangeably.
If you want to use a hostname that is not DNS resolvable to
reference your Exos enclosure within LINSTOR, you may use any name in
place of <exos_hostname> , but you will also have to supply the
enclosure’s IP address: linstor node create <desired_name> <enclosure_ip>
|
Use the following example to create and inspect the current controller settings:
# linstor exos create Alpha 172.16.16.12 172.16.16.13 # linstor exos list +------------------------------------------------------------------+ | Enclosure | Ctrl A IP | Ctrl B IP | Health | Health Reason | |==================================================================| | Alpha | 172.16.16.12 | 172.16.16.13 | OK | | +------------------------------------------------------------------+
For a more in-depth view, you can always ask the LINSTOR controller
or the LINSTOR nodes for the Exos
-related properties:
# linstor controller list-properties | grep Exos | StorDriver/Exos/Alpha/A/IP | 172.16.16.12 | | StorDriver/Exos/Alpha/B/IP | 172.16.16.13 |
13.2.3. Creating Node to Enclosure to Pool Mapping
A LINSTOR Satellite node can be created as usual.
# linstor node create <satellite_hostname>
The storage pool can also be created as usual in LINSTOR. Only the name of the previously registered Exos enclosure as well as the serial number of the Exos pool needs to be specified:
# linstor storage-pool create exos \ <satellite_hostname> <linstor_pool_name> <exos_encl_name> <exos_pool_sn>
the linstor_pool_name can be set to (almost) any unique string for the LINSTOR deployment.
Here is an example of mapping an Exos Pool in Exos enclosure Alpha to two Satellite nodes:
# linstor storage-pool create exos \ node1 poolA Alpha 00c0ff29a5f5000095a2075d01000000 # linstor storage-pool create exos \ node2 poolA Alpha 00c0ff29a5f5000095a2075d01000000
After creating an exos
storage pool the LINSTOR Satellite will scan
the given Exos enclosure for connected ports. If cabled, these ports will be
listed in the following command:
# linstor exos map -p +----------------------------------------------+ | Node Name | Enclosure Name | Connected Ports | |==============================================| | node1 | Alpha | A0, B0 | | node2 | Alpha | A1, B1 | +----------------------------------------------+
The pool configuration is shown by:
hr01u09:~ # linstor sp list -s poolA -p +----------------------------------------------------------------------------------------------+ | StoragePool | Node | Driver | PoolName | FreeCapacity | ... | |==============================================================================================| | poolA | node1 | EXOS | Alpha_00c0ff29a5f5000095a2075d01000000 | 581 TiB | ... | | poolA | node2 | EXOS | Alpha_00c0ff29a5f5000095a2075d01000000 | 581 TiB | ... | +----------------------------------------------------------------------------------------------+
Detailed description of all the available Exos commands is found with built-in help.
# linstor exos -h
13.3. Creating Resources Backed by Exos Storage Pools
Creating LINSTOR resources from Exos backed storage-pools follows normal LINSTOR usage patterns as described in other sections of the LINSTOR User’s Guide such as the sections describing LINSTOR resource groups or the more granular resource-definition, volume-definition, resource creation workflow.
14. LINSTOR Volumes in CloudStack
This chapter describes using LINSTOR to provision volumes that can be used to back primary storage in Apache CloudStack. CloudStack primary storage stores the virtual disks for virtual machines (VMs) running on hosts in CloudStack. A LINBIT-developed CloudStack plug-in integrates LINSTOR with CloudStack. A benefit to integrating LINSTOR with CloudStack is that it can be a way to provide highly available primary storage that is also flexible to manage.
Currently, the LINSTOR plug-in for CloudStack can only be used to provision volumes for use with KVM hypervisors. |
Setting up and deploying CloudStack can be a complex task. A production-ready deployment can take several weeks to months before it is ready for users. A basic test deployment in a virtual environment can be set up in a few hours perhaps. This chapter will deal only with aspects related to integrating LINSTOR in CloudStack and should be considered a general overview. You should supplement instructions in this chapter with instructions and best practice recommendations from the CloudStack documentation.
Attention should be paid to security, firewall, and resource provisioning instructions in the CloudStack documentation, and in other chapters in the LINSTOR User’s Guide, before production deployment. |
In this chapter, as in other areas of the LINSTOR User’s Guide, the word node is used. In most cases, you can think of a node as equivalent to a CloudStack host. |
14.1. Introduction to CloudStack
From the CloudStack documentation: “Apache CloudStack is an open source Infrastructure-as-a-Service (IaaS) platform that manages and orchestrates pools of storage, network, and computer resources to build a public or private IaaS compute cloud.”
14.2. Preparing Your Environment For CloudStack and LINSTOR Deployment
You will need to make a few preparatory steps before deploying LINSTOR for use with CloudStack.
14.2.1. Configuring Time Synchronization
It is important that the nodes in your cluster are time synchronized. To do this, you can install and configure a tool such as Chrony or OpenNTPD.
14.2.2. Adding Node IP Addresses and Host Names
Add your cluster nodes’ IP addresses and host names to each node’s /etc/hosts
file.
14.3. Installing and Preparing LINSTOR for CloudStack
The LINSTOR plug-in is included in Apache CloudStack versions 4.16.1 and later. You do not have to install anything else to support LINSTOR. CloudStack versions 4.16.0 and earlier do not support the LINSTOR plug-in.
One of the pull requests did not merge properly in CloudStack v4.17.0 which caused a CloudStack UI bug in the CloudStack initialization wizard. More details are available here. If you need to be on the v4.17 branch, it is recommended (at time of writing) that you install v4.17.1. |
Follow the installation instructions in the LINSTOR User’s Guide to install LINSTOR on the storage providing nodes in your cluster.
A basic outline of installation steps is:
-
Install necessary packages for storage layers that you will be using, for example, ZFS or LVM. The steps below use ZFS as a backing storage layer for LINSTOR.
-
Install the necessary LINSTOR packages (DRBD kernel module,
linbit-sds-controller
, andlinbit-sds-satellite
packages) from LINBIT repositories if you are a LINBIT customer, otherwise, you will need to build from source. -
Restart the
multipathd
daemon.systemctl restart multipathd
-
Enable and start the LINSTOR Controller and LINSTOR Satellite services on your nodes.
# systemctl enable --now linstor-controller # systemctl enable --now linstor-satellite
-
Add your nodes to LINSTOR.
linstor node create <node_host_name>
-
Create a new LINSTOR storage pool on all of your participating nodes. For example, given a ZFS pool named
zfs_storage
, enter the following to create a storage pool namedDfltStorPool
:# linstor storage-pool create zfs <node_host_name> DfltStorPool zfs_storage
-
Create a LINSTOR resource group to be used for CloudStack. To create a resource group named
cloudstack
, to be placed on two of your cluster nodes, enter:# linstor resource-group create cloudstack --place-count 2 --storage-pool DfltStorPool
-
Create a LINSTOR volume group from your resource group, by entering the command:
# linstor volume-group create cloudstack
14.3.1. Verifying Creating Resources
After installing LINSTOR and creating a resource group backed by a storage pool and storage layer, test that you can create storage resources. You can do this by spawning resources from the resource group that you created.
The CloudStack setup best practices recommend that a primary storage mount point (and therefore the LINSTOR resource that backs it) “should not exceed 6TB in size.” |
# linstor resource-group spawn cloudstack testres 1GiB
Verify that LINSTOR created your resources by using a resource list
command.
# linstor resource list +----------------------------------------------------------------------------------+ | ResourceName | Node | Port | Usage | Conns | State | CreatedOn | |-=================================================================================| | testres | node-0 | 7000 | Unused | Ok | UpToDate | 2022-11-10 20:12:30 | | testres | node-1 | 7000 | Unused | Ok | UpToDate | 2022-11-10 20:12:30 | | testres | node-2 | 7000 | Unused | Ok | TieBreaker | 2022-11-10 20:12:29 | +----------------------------------------------------------------------------------+
14.4. Installing CloudStack
After installing and preparing LINSTOR, you can install and configure CloudStack. As disclaimed previously, you should take these instructions as a way to setup CloudStack quickly for testing and illustrative purposes. Refer to CloudStack documentation for detailed instructions and best practice recommendations, before deploying into production.
14.4.1. Installing MySQL
First, install a MySQL server instance that is necessary for CloudStack’s database.
On Ubuntu, enter:
# apt install -y mysql-server
On RHEL, enter:
# dnf install -y mysql-server
14.4.2. Configuring the CloudStack Database
After installing the MySQL server package, create a CloudStack database configuration file named
/etc/mysql/conf.d/cloudstack.cnf
with the following contents:
[mysqld] innodb_rollback_on_timeout=1 innodb_lock_wait_timeout=600 max_connections=350 (1) log-bin=mysql-bin binlog-format = 'ROW'
1 | 350 is the max_connections value specified in
the
CloudStack installation guide. You can change this value depending on your needs. |
If you are on an Ubuntu 16.04 or later system, for binary logging, you need to
specify a server_id
in your .cnf
database configuration file, for example:
[mysqld] server_id = 1 innodb_rollback_on_timeout=1 innodb_lock_wait_timeout=600 max_connections=350 log-bin=mysql-bin binlog-format = 'ROW'
Then restart the MySQL service by entering systemctl restart mysql
.
14.4.3. Installing NFS for Secondary Storage
Next, install and configure NFS for CloudStack’s secondary storage. You only need to do this on the node that will be your CloudStack management node. CloudStack uses secondary storage to store such things as operating system images for VMs and snapshots of VM data.
To install NFS, on Ubuntu, enter:
# apt install -y nfs-kernel-server
On RHEL, enter:
# dnf install -y nfs-utils
After installing the NFS server, create an NFS export for CloudStack’s secondary storage by entering the following commands:
# mkdir -p /export/secondary # echo "/export *(rw,async,no_root_squash,no_subtree_check)" >> /etc/exports # exportfs -a
Next, enable and start the NFS server service.
# systemctl enable --now nfs-server
14.5. Installing and Configuring CloudStack
General CloudStack installation and configuration instructions follow. As your environment may have specific needs or variations, you should also reference the instructions in the CloudStack Installation Guide.
14.5.1. Installing CloudStack
While official CloudStack releases are “always in source code form,” for convenience, there are community generated DEB and RPM packages available at cloudstack.org:
-
Ubuntu DEB repository: http://download.cloudstack.org/ubuntu
-
EL8 RPM repository: http://download.cloudstack.org/el/8/
-
EL7 RPM repository: http://download.cloudstack.org/el/7/
You can follow the links above to find and download the packages that you need for your installation. Be sure to verify the integrity of downloaded packages against CloudStack’s signing keys, as outlined in the instructions here.
Alternatively, you can follow instructions here to configure the CloudStack repository appropriate to your Linux distribution and then pull and install packages by using your distribution’s package manager.
After adding the CloudStack repository, you may need to update the package manager’s repository list, before you can install packages.
For your CloudStack management node, install these packages:
-
cloudstack-management
-
cloudstack-common
-
cloudstack-ui
For your other cluster nodes that will be hosting VMs, install the cloudstack-agent
package.
14.5.2. Initializing the CloudStack Database
After installing the necessary CloudStack packages, initialize the CloudStack database.
For testing purposes, you can enter the following command on your management node:
# cloudstack-setup-databases cloud:cloud --deploy-as=root:nonsense -i <node_name>
Here, the cloud
after cloud:
and nonsense
are passwords that you can change as you see
fit.
For production deployments, follow the more detailed instructions in the CloudStack Installation Guide.
14.6. Installing the CloudStack System Virtual Machine Image Template
CloudStack needs to run some system VMs for some of its functionality. You can download a CloudStack VM template image and then run a CloudStack script that will prepare the image for various system VMs in deployment. On the CloudStack management node, enter the following commands:
# CS_VERSION=4.17 # CS_VERSION_PATCH=4.17.1 # wget https://download.cloudstack.org/systemvm/$CS_VERSION/systemvmtemplate-$CS_VERSION_PATCH-kvm.qcow2.bz2 # /usr/share/cloudstack-common/scripts/storage/secondary/cloud-install-sys-tmplt \ -m /export/secondary \ -f systemvmtemplate-$CS_VERSION_PATCH=-kvm.qcow2.bz2 \ -h kvm -o localhost -r cloud -d cloud
14.7. Configuring KVM Hypervisor Hosts for Use in CloudStack
Currently, the LINSTOR CloudStack plug-in only supports KVM hypervisor hosts. The instructions that follow are for configuring your CloudStack installation with KVM hypervisor hosts.
Enter the following command to add libvirt
configurations to every node in your cluster that
will host CloudStack VMs:
# cat << EOF >> /etc/libvirt/libvirtd.conf listen_tls = 0 listen_tcp = 1 tcp_port = "16509" auth_tcp = "none" # not suitable for production mdns_adv = 0 EOF
Restart the libvirtd
service on all hypervisor nodes.
# systemctl restart libvirtd
14.7.1. Configuring AppArmor
If you are running CloudStack on Ubuntu Linux and if AppArmor is enabled, enter the following:
# ln -s /etc/apparmor.d/usr.sbin.libvirtd /etc/apparmor.d/disable/ # ln -s /etc/apparmor.d/usr.lib.libvirt.virt-aa-helper /etc/apparmor.d/disable/ # apparmor_parser -R /etc/apparmor.d/usr.sbin.libvirtd # apparmor_parser -R /etc/apparmor.d/usr.lib.libvirt.virt-aa-helper
14.7.2. Restarting the CloudStack Management Service
After making the necessary setup and preparatory configurations, restart the
cloudstack-management
service.
# systemctl restart cloudstack-management
You can follow the progress of CloudStack’s initial database setup by entering:
# journalctl -u cloudstack-management -f
14.7.3. Logging into the CloudStack UI
After some time, you should be able to log into the CloudStack management UI. Given a management
node resolvable host name of node-0
, enter the following URL into a web browser on a computer in
your cluster’s network: http://node-0:8080/client
.
Once you are greeted by the CloudStack UI’s portal login page, log into the portal by using the
default user name admin
and the default password password
.
After successfully logging in, the CloudStack UI will display the “Hello and Welcome to CloudStack” page.
14.7.4. Running the CloudStack Initialization Wizard
You can continue to set up CloudStack by launching an initialization wizard. Click on the “Continue with installation” button to launch the wizard.
The wizard will first prompt you to change the default password for the administrator user. After changing the password, you can continue through the wizard steps to configure a zone, network, and resources details. Complete the fields in each setup step according to your environment and needs. More details about initializing CloudStack can be found here.
The following fields will be common to all LINSTOR use cases in CloudStack:
-
Zone details:
-
Hypervisor: KVM
-
-
Add resources, IP Address step:
-
Host Name: <host_name_of_cluster_node_that_will_host_VMs>
-
Username: root
-
Password: <root_password_that_you_configured_previously_for_the_host>
-
-
Add resources, Primary Storage step:
-
Protocol: Linstor
-
Server: <IP_address_of_LINSTOR_controller_node>
-
Resource Group: <LINSTOR_resource_group_name_that_you_configured_previously>
-
Based on configuring an NFS export for secondary storage earlier, complete the fields presented during the “Add resources, Secondary Storage” step as follows:
-
Provider: NFS
-
IP Address: <IP_address_of_NFS_server> # should be the CloudStack management node
-
Path: <NFS_mount_point> #
/export/secondary
, as configured previously
After completing entry fields in the “Add resources” fields and clicking the “Next” button, the wizard will display a message indicating the “Zone is ready to launch.” Click on the “Launch Zone” button.
The “Adding Host” step of the “Launch Zone” process may take a while. |
After the zone is added, the wizard will show a “Zone creation complete” message. You can then click on the “Enable Zone” button. After another “Success” notification you will be returned to the CloudStack UI dashboard.
14.8. Taking Next Steps in CloudStack
After configuring LINSTOR for use in CloudStack you can move onto other tasks, such as adding hosts to host your CloudStack VMs.
LINBIT has also made available a video demonstrating deploying LINSTOR and CloudStack into a three-node VM cluster. You can view the video here.
15. LINSTOR Volumes in Oracle Linux Virtualization Manager
This chapter describes using LINSTOR to provision persistent, replicated, and high-performance block storage for Oracle Linux Virtualization Manager.
15.1. Introduction to Oracle Linux Virtualization Manager
Oracle Linux Virtualization Manager (OLVM) is a server virtualization management platform based on oVirt. It can configure, manage and monitor a Kernel-based Virtual Machine (KVM) environment based on Oracle Linux.
OLVM supports multiple storage technologies that can be integrated with LINSTOR:
-
iSCSI or NFS storage are used for shared storage. In this setup, all OLVM nodes connect to a service host that exports the storage volume, by using iSCSI or NFS. Here, LINSTOR Gateway can help you create and manage iSCSI targets and NFS exports based on replicated DRBD volumes and make them highly available.
-
Managed Block Storage is another feature available in OLVM. Disks for VMs are managed as separate volumes, rather than from within a pool of storage on a service host. This makes it possible to directly attach a volume to a VM while avoiding the performance overhead that a service host adds.
15.2. Using LINSTOR Gateway for OLVM Storage
LINSTOR Gateway creates highly available iSCSI targets and NFS exports, which OLVM can consume as data domains. All volume access is routed through the LINSTOR Gateway host exporting the volume. Volume access includes reads and writes by any VM using the storage domain.
As prerequisites, you need:
-
A working LINSTOR Cluster, with High Availability enabled.
-
A working LINSTOR Gateway installation.
LINSTOR and LINSTOR Gateway don’t need to run on the same nodes as OLVM, provided that the Gateway nodes are reachable from the OLVM hosts. |
15.2.1. Using LINSTOR Gateway for Data Domains
Data Domains are the primary storage for your VMs in OLVM. With LINSTOR Gateway, you can create both iSCSI targets and NFS exports, to use as Data Domains in OLVM.
Use the linstor-gateway
command to create iSCSI or NFS exports. Choose a service IP that is reachable from the OLVM
nodes. The following example creates an iSCSI export of 60GB reachable under 192.168.0.100
and a NFS export of 50GB,
available at 192.168.0.101:/srv/gateway-exports/nfs-data
$ linstor-gateway iscsi create iqn.2019-08.com.linbit:data-domain 192.168.0.100/24 60G Created iSCSI target 'iqn.2019-08.com.linbit:data-domain' $ linstor-gateway nfs create nfs-data 192.168.0.101/24 50G Created export 'nfs-data' at 192.168.0.101:/srv/gateway-exports/nfs-data
To configure the storage domains, navigate to the OLVM Administration Portal and open the Storage > Domains
page.
Click New Domain
and choose a name for the new storage domain. Then, select the Domain function (either Data
or
ISO
) and the matching storage type (either iSCSI
or NFS
). Enter the required connection parameters to complete
the configuration.
15.2.2. Using LINSTOR Gateway to Deploy the OLVM Self-Hosted Engine
LINSTOR Gateway iSCSI Targets can be used to create the initial data domain used when deploying the OLVM self-hosted engine.
Use a separate data domain for the self-hosted engine to reduce the risk of adverse interference with your VMs. Create
a iSCSI target with at least 60GB to use for the management VM. The following example creates a 60GB volume exported as
iqn.2019-08.com.linbit:olvm-engine
, available at the IP 192.168.0.200
. Change the IP and iSCSI target name to
appropriate values for your setup.
$ linstor-gateway iscsi create iqn.2019-08.com.linbit:engine-data 192.168.0.200/24 60G
While setting up the OLVM self-hosted engine, you will be asked to provide details for the storage of the Manager
virtual machine. You only need to provide the storage type iscsi
and the IP address 192.168.0.200
. All other
information will be discovered automatically.
Please specify the storage you would like to use (glusterfs, iscsi, fc, nfs)[nfs]: iscsi Please specify the iSCSI portal IP address: 192.168.0.200 Please specify the iSCSI portal port [3260]: Please specify the iSCSI discover user: Please specify the iSCSI discover password: Please specify the iSCSI portal login user: Please specify the iSCSI portal login password: The following targets have been found: [1] iqn.2019-08.com.linbit:engine-data TPGT: 1, portals: 192.168.0.200:3260 Please select a target (1) [1]: 1 Please select the destination LUN (1) [1]:
After the setup completes, the iSCSI target is added as a data domain to OLVM. Use separate data domains for your VMs to avoid interference with the self-hosted engine’s storage.
15.3. Using LINSTOR Cinder for Managed Block Storage
OLVM can be configured to use the LINSTOR Cinder driver to attach LINSTOR managed volumes directly on the VM host. In contrast to using LINSTOR Gateway, storage access and replication happens directly from the host the VM is running on.
Using LINSTOR Cinder requires several additional steps to set up for OLVM:
-
All OLVM hosts, including the engine host, need to be registered with LINBIT and the
ovirt
repository enabled:# curl -O https://my.linbit.com/linbit-manage-node.py # chmod +x ./linbit-manage-node.py # ./linbit-manage-node.py ... 1) pacemaker-2(Disabled) 2) ovirt(Enabled) 3) drbd-9.0(Disabled) 4) drbd-9(Enabled) ...
-
OLVM hosts as well as the management engine need to be part of the LINSTOR cluster. Ensure that the
linstor-satellite
service is installed and configured on all hosts. -
OLVM needs to have
CinderLib
support enabled. It is disabled by default. To enable it, runengine-setup
on the engine host:$ engine-setup --reconfigure-optional-components ... --== PRODUCT OPTIONS ==-- Configure Cinderlib integration (Currently in tech preview) (Yes, No) [No]: Yes ...
-
The engine hosts need to have the LINBIT version of
python3-cinder-common
installed, which can be identified by thelinbit1
string in the version number:$ dnf install --enablerepo=ovirt python3-cinder-common $ dnf list --installed python3-cinder-common Installed Packages python3-cinder-common.noarch 1:17.2.0-1.el8.linbit1 @linbit-ovirt
-
The engine hosts need to have the
linstor-cinder
package installed:$ dnf install --enablerepo=ovirt linstor-cinder
-
All OLVM hosts need to have the LINBIT version of
vdsm
andpython3-osbrick
installed, which can be identified by thelinbit1
string in the version number:$ dnf install --enablerepo=ovirt vdsm python3-os-brick $ dnf list --installed vdsm python3-os-brick Installed Packages python3-os-brick.noarch 4.0.4-1.el8.linbit1 @linbit-ovirt vdsm.x86_64 4.40.100.2-1.0.13.el8.linbit1 @linbit-ovirt
To configure LINSTOR Cinder for Managed Block Storage, navigate to the OLVM Administration Portal and open the
Storage > Domains
page. Click New Domain
and select Domain Function “Managed Block Storage”. Choose a name, and set
the following driver options:
Driver Option |
Value |
|
|
|
URL of the LINSTOR Controller Endpoint(s). Separate multiple endpoints by using a comma ( |
|
LINSTOR resource group to use. Volumes created in this data domain will inherit all settings on the resource group. |
OLVM 4.4 does not support creating VMs using Managed Block Storage from the VM Portal, only through the Administration Portal. |
.res
resource files. However, property changes made on the parent are not copied to the child objects (either the resource definition or resource LINSTOR objects), that is, the child objects do not carry the property themselves. The change affects the object children, but the property itself remains on the parent.