Running Fedora Cloud images on KVM

Inspired by Matt’s blog post I’ve decided to make something that is similar but better fits my use case. I plan to do some clustering and routing testing and therefore I need to have similar VMs running side-by-side. These images will be short-lived and I would like to automate as many things I can.

Additionally, I found out that the images shipped by Fedora require some changes to work well in my case, for example the default 2GB disk is too small.

Script

You can see my script here.

My script does create a new domain with the desired name with the cloud disk image. I use the a QCOW2 image to not eat all the free space on my SSD. The disk can be optionally grown to the desired size. The whole install is done without VNC using the text method. The domain is optionally run after the setup completes.

I use the cloud-init script only for the initial setup (setting the password) - afterwards it is removed from the image. The same thing happens to the ISO used for the cloud-init configuration - it’s ejected and removed from the disk afterwards.

Sample run

$ virt-install-fedora host
Thu, 16 Jan 2014 14:28:58 +0100 Destroying the host1 domain...
Thu, 16 Jan 2014 14:28:59 +0100 Generating ISO for cloud-init...
Thu, 16 Jan 2014 14:28:59 +0100 Installing the domain and adjusting the configuration...
Thu, 16 Jan 2014 14:29:23 +0100 Cleaning up cloud-init...
Thu, 16 Jan 2014 14:29:23 +0100 Resizing the disk...
Thu, 16 Jan 2014 14:30:15 +0100 Launching the host1 domain...
Thu, 16 Jan 2014 14:30:15 +0100 DONE, ssh to the 192.168.122.43 host using 'fedora' username and 'fedora' password

After about a minute I have a registered domain with a Fedora 20 disk image on a 20GB QCOW2 disk. Pretty good. And I can run the command as many times I want to deploy new VMs.

Along with the disk image — the script creates a log file (in my case host1/host1.log) in which you can see the messages from the commands that were run during the installation.

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