Windows – XenServer for NAS and Virtualization

Debian or Ubuntu are both suitable choices for your xen dom0.

As for resources, it's difficult to give strict recommendations because no two setups are the same and ultimately it depends on what your guests are going to be doing.

First up, you won't have all the memory in the physical system available for use in dom0 and your other guest. Xen will take a slice of the memory for itself. The more physical memory, the more xen will need.

The amount of dom0 memory you're going to need depends on the workload it's going to be handling with management of the guests and all the I/0 from the guests. It's difficult to quantify. 512MB may well be enough. In any case you can change if that isn't sufficient.

At a previous job we integrated xen server into our virtualisation platform. Dom0 was set to 768M, which did the job and I didn't come across any instances of this being exhausted by customers. This was on physical boxes with upto 64GB of memory. Another approach is to give all the available memory to dom0, and then slice chunks off each time you create a guest.

Here are my first, second, and third blog posts on running XenServer on commodity hardware. Eventually, I scored an amazing deal on a Dell Poweredge T110 for under $350, and moved off of the commodity hardware to server class--And I have never looked back!

Hope it gives you some ideas-

-Josh