Archive for April, 2012

Ubuntu 12.04 HA infrastructure

Friday, April 27th, 2012

Ready for high availability in Ubuntu 12.04?! :)

High availability in Linux has seen lots of changes in recent years. This is a result of an effort to merge most relevant HA stacks in Linux world – RedHat Cluster Suite and Linux-HA. Work upstream did on this is tremendous and one can only congratulate on that. Unfortunately, for us following this development, that meant we had to keep track with all those changes in the code and configuration. That’s why, for 10.04, we had official packages in the distribution and backported and supported packages in ubuntu-ha-maintainers PPA. We hope that for 12.04 PPA will not be required any more :)

HA in Ubuntu is based on Pacemaker 1.1.6. One can use both GFS2 and/or OCFS2 shared filesystems on top of shared storage (DRBD or any other type of shared hardware storage).

To make deploying HA easier for users and system administrators, we’ve started a WIKI explaining most common setups. At the moment, this wiki covers only how to initially setup GFS2 and OCFS2 shared filesystems on a shared storage. In few days, we’ll add guides for DRBD, cLVM and guides for some migration scenarios – 10.04 -> 12.04; 10.04 +  PPA -> 12.04, etc.

Important: We’ve encountered couple of bugs that are in the queue for fixing. If you are using or have a desire of using cLVM, please do not use 12.04 yet. Once these fixes land into archives, we’ll send an email to ubuntu-ha mailing list and add cLVM howto to the wiki.

Ubuntu 12.04 Cloud Live

Friday, April 27th, 2012

With the release of Ubuntu 12.04, it’s time to release Cloud Live image too! Cloud Live is a live CD/USB image that allows you to get a glimpse of Ubuntu Cloud Infrastructure. Project’s web site is located at Launchpad – https://launchpad.net/cloud-live. Procedure is very simple; download an image, burn it on CD or dd it on the USB key and boot of that device. System will boot in Unity or Unity2D and present you with at Getting Started document. Notice that we do not include full Ubuntu desktop experience – we’ve removed all components that aren’t necessary for this project, to make image as small as possible.

Once you finish with Getting Started document, you’ll be able to log into the dashboard and start instances. All of this without installing anything on your computer! For the purpose of demo, we’ve provided a small CirrOS image which you can run and log in to. Since everything is running in RAM, you will have better experience if your system has 4 or more gigabytes of memory. 2GB is enough to get system booted, but you won’t be able to do much more after that.

For a little extra, we’ve configured Ubuntu Cloud Live with support for Nova Volume. All you have to do is plug in additional disk, create a PV volume on it (pvcreate /dev/xyz), create nova-volumes VG (vgcreate nova-volumes /dev/xyz) and restart nova volume (service nova-volume restart).

Image is built with live-build and the source is available on Launchpad. Build process pulls in one package that’s also available on Launchpad. Procedure for building your own Cloud Live is very simple:

  1. Install Ubuntu 12.04, 64bit
  2. Install live-build package
  3. Create working directory – mkdir ~/cloud-live ; cd ~/cloud-live
  4. Branch bzr code – bzr branch lp:cloud-live config
  5. [OPTIONAL] Customize config/* files
  6. Build an image – sudo lb build
  7. Burn or dd resulting image – binary-hybrid.iso

Or, if you just want default, official, Ubuntu Cloud Live image, go to cdimage.ubuntu.com and grab it!