I had to spend some time setting up Xen on one of the new Dell servers we bought and while there was some documentation around, I had to constantly refer to the different sources since there wasn’t a complete page which had everything I needed for my particular situation - I have a host machine with Ubuntu Feisty Fawn installed and wanted to install a couple of Xen guest domains on it. One other thing I found lacking in the documentation is the explanation of commands or answers to the question “so why the hell am I doing this?”. I’m not considering LVM at the moment and am happy with loopback disk file images too.
So I think it’s a good idea to write this down somewhere for the next time I have to do the same bloody thing over again on any new servers.
Some caveats before we start:
Like I said, I’m not gonna talk about LVM for disk images since I know next to nothing about configuring it at the moment. The host machine I have isn’t setup with LVM and I haven’t got the time to look into LVM either.
I’m quite the networking newbie, so my setup uses the default Xen bridge installed via apt-get. Check out Xen networking on the Xen wiki for more complex network setups.
I’m not gonna talk about putting a Linux distro other than that of the host machine into the Xen virtual machines. In other words, I have Feisty Fawn for both dom0 and all my domUs.
I probably did some completely stupid things. Stuff like xen-tools exist to simplify Xen administration, but I haven’t had a chance to use them. Let me know if you spot an error or have a better way of doing something please!
Some terms that deserve explaining (most guides out there just use “DomU” and “Dom0″ without any ceremony, and assume you know what they mean):
Domain-0 or Dom0: This refers to the host machine OS. You know, the OS of the actual physical server that you have.
DomU: This refers to a Xen guest domain. A DomU is a single Xen virtual machine. The “U” stands for “unprivileged” I believe.
OK let’s go!
