I may be wrong on this compdoc, but I'm pretty sure it's a pretty bad idea
to have the host (Dom0 for me, in Xen) doing anything other than hosting the system for the DomUs.
Thanks for the reply, but someone else asked the question. I use KVM and the host isn't taxed to the point of needing to be strictly a host. One trick I've learned: have the OS, VMs, and large storage on separate physical drives, or it can choke.
This is also what helps facilitate backups and maintenance. For instance I can remove the OS drive, pop in a new drive and load a new OS and test the whole thing. If something goes south, I can reinstall the old OS drive and be up and running in a few minutes. If nothing goes wrong, I just hold the old drive for a while as backup, then recycle it in a new project at some point.
By the way, I've tried openfiler in a VM, (citrix zenserver or kvm) as well as on dedicated hardware. I found it would just stop responding and had to be rebooted after a few weeks of use. And this was with different versions of openfiler, since I keep thinking newer versions would fix the problems...