Since my last post (in amongst family and work and stuff) I've been playing with Xenserver and the N40L Microserver. Here's how it's gone down:
The initial install went quite well, except I had configured two mirrored RAID arrays - one with 2 x 1TB disks, the other with 2 x 2TB disks. Xenserver saw neither of them. So I removed both arrays, set the SATA controller back to AHCI and went from there.
After a quick re-install, I had an initial local storage of 1TB. Following this I added three more local storage devices and re-thought how I was going to do the installation of my VMs. Following the exceptional directions on creating an Ubuntu 12.04LTS server on Xenserver from http://www.invalidlogic.com/2012/05/01/deploying-ubuntu-12-04-on-xenserver-made-easy I created a 12.04 Ubuntu virtual server - all went very well. In accordance with my plan, I also created a Windows Home Server 2011 using the Windows 2008R2 template.
The WHS2011 server was so slow to install, setup and run. I had assigned it 2 CPU's, 4GB of RAM and it took at least three hours longer than the Ubuntu server to install and get going. I must note that the template from invalidlogic.com was superb and perhaps that has spoilt me a bit :-)
I also set up a FreeNAS - installed to one of the 1TB drives with 2 x 2TB virtual disks presented to it. The FreeNAS server installed quite fast and everything looked good. I set up NFS and CIFS shares and thought it was all going well. Unfortunately, as soon as I started to copy data across to the FreeNAS it's CPU usage hit 100% (as did the host's CPU). This was clearly a failure and wasn't going to work.
Undeterred, I thought about Dragonfly BSD and the excellent HAMMER file system - let's give that a crack I thought. The initial boot of the disk failed.... So FreeNAS and Dragonfly aren't going to play the game - new plan! More about this tomorrow :-)