Raspberry Tau: a Pi cluster

LINBIT featured image

The Raspberry PI is a small ARM computer (hardware specifications in wiki, outline and FAQs). Of course, you can build a cluster with it!

As 2π is proposed to be named τ we’ve chosen the name “Raspberry Tau” for this proof-of-concept.

We’ve connected two Raspberry Pis via their on-board ethernet interfaces (via a switch, so we can simply SSH into them), booted via 2GB SD-cards with a Raspbian image on them. After upgrading to a kernel that has kernel-headers available we built DRBD® modules, and voilá! A Raspberry Tau cluster is born.

We’re replicating the data on the USB-Sticks; their performance nicely matches the available network. Here’s /proc/drbd (shortened and line-wrapped for readability):

root@raspberry-alice:~# cat /proc/version 
Linux version 3.2.0-3-rpi (Debian 3.2.21-1+rpi1) 
  (debian-kernel@lists.debian.org) (… Debian 4.6.3-1.1+rpi2)…)
root@raspberry-alice:~# cat /proc/drbd 
version: 8.4.2 (api:1/proto:86-101)
GIT-hash: 7ad5f850d711223713d6dcadc3dd48860321070c build by
    root@raspberry-bob, 2012-09-18 12:58:08
 0: cs:Connected ro:Primary/Secondary ds:UpToDate/UpToDate C r-----
    ns:805304 nr:0 dw:348628 dr:818596 al:127 bm:70 lo:0 pe:0
      ua:0 ap:0 ep:1 wo:d oos:0

As Raspbian is Debian-based, there are Pacemaker (and Heartbeat resp. Corosync) packages available … so a cheap, low-power, High-Availability cluster is easily built.

Disclaimer: for a real HA-cluster you’d need a few more things.

  • a STONITH device (if power is supplied via a Linux-PC, you could turn off the USB port by software), and
  • redundant network connectivity (USB ethernet adapter).

Of course, if you’re just clustering your media library these things might not be mandatory.

Packages are available for everyone – just drop an email to sales@linbit.com, and we will be happy to provide them. Please note that the upstream kernels already include the DRBD kernel module, so there’s no need to compile your own – unless you want to test the cutting edge; in that case, good luck 😉

Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on whatsapp
Share on vk
Share on email

Share this post

Yusuf Yıldız

Yusuf Yıldız

After nearly 15 years of system and storage management, Yusuf started to work as a solution architect at Linbit. Yusuf's main focus is on customer success and contributing to product development and testing. As part of the solution architects team, he is one of the backbone and supporter of the sales team.

Talk to us

LINBIT is committed to protecting and respecting your privacy, and we’ll only use your personal information to administer your account and to provide the products and services you requested from us. From time to time, we would like to contact you about our products and services, as well as other content that may be of interest to you. If you consent to us contacting you for this purpose, please tick above to say how you would like us to contact you.

You can unsubscribe from these communications at any time. For more information on how to unsubscribe, our privacy practices, and how we are committed to protecting and respecting your privacy, please review our Privacy Policy.

By clicking submit below, you consent to allow LINBIT to store and process the personal information submitted above to provide you the content requested.

Talk to us

LINBIT is committed to protecting and respecting your privacy, and we’ll only use your personal information to administer your account and to provide the products and services you requested from us. From time to time, we would like to contact you about our products and services, as well as other content that may be of interest to you. If you consent to us contacting you for this purpose, please tick above to say how you would like us to contact you.

You can unsubscribe from these communications at any time. For more information on how to unsubscribe, our privacy practices, and how we are committed to protecting and respecting your privacy, please review our Privacy Policy.

By clicking submit below, you consent to allow LINBIT to store and process the personal information submitted above to provide you the content requested.