@Danp
So, that's the "best" way? Backup the meta-data with XOA, rebuild the OS drive - add the "new" server into XOA and restore the meta-data back to the new install?
(I'm not doubting it is, just wanting to be sure we're understanding each other fully.)
Seems straight-forward - but there's a ton of things I've done over the years that "seemed" pretty straight-forward that turned out to be anything but, and at least occasionally found I had no way back. 
I stupidly assumed that the HP servers I built two of my XCP boxes on would allow me to move the single boot drive to RAID1 without any data loss. Sadly, I assumed badly.
So, to get the XCP boot disk into a fault-tolerant RAID1 state, I'll have to destroy the boot disk and rebuild the OS.
The VM's are on separate disks, so I'm not worried about them very much - they should be just fine, provided I don't do something stupid while rebuilding the boot disks. (I'll have backup of the VM's too, just in case.)
So, what's the best way to go about getting things back up?
Obviously I'll have to handle all the steps to get it onto RAID1, and XCP booting up again. That's "easy".
But then I need to "reimport" all the meta-data for the VM's so the system knows their names, locations, etc. (I have an XOA meta-data backup occurring too, but I'd assume there's a way we don't have to use that, right?)
Is there an article on this somewhere? (I'd assume this is largely covered for a disaster recovery situation, so there must be some coverage somewhere... Even an "upgrade" does something similar, I think, when it backs up the "old" system before running the upgrade..)
TIA
-Greg