We have successfully installed ESXi 5.1 on an Xserve (early 2009) and have mountain lion server running flawlessly. We're using our Equallogic san to give it large volumes for video storage and editing (FCP, Premier, AE). We're still experimenting with vmdk vs RDM though.
I dont have a 2nd Xserve to test vMotion, et al... but thats the next phase of our project.
Issues so far:
no hot-add/resize for virtual disks - best I understand, the virtual LSI Parallel SCSI adapter is treated as old school SCSI, and cannot be rescanned without a restart.
CPU meter on the front panel doesn't work (I list this half jokingly... its really the only other complaint I have so far)
Anyone else have experience with this setup?
Any potential problems to watch out for?
Any thoughts on whether to use vmdk vs rdm?
Has anyone researched the licensing implications? It looks like only 2 lion guests are allowed per host... but can you buy more licenses?