This is important stuff, especially if your new to it like I am, and don't have the budget for iSCSI, SAN or whatever else is out there.
Have a backup of the data on the VM.
Raid is not a VM Data backup.
Have a backup of the VM.
Raid is not a VM VHD backup.
Have a backup of the Host machine.
Raid is not a backup of a Server.
Have notes on all the machines, including at least the following and anything else you care and if you have extra please email them to me at firstname.lastname@example.org.NOSPAM -
IP's of all the machines both virtual and Physical.
Server names, FQDN and Netbios.
An odd one, but how long the physical machine needs to reboot, trust me, if your sitting there waiting for a machine to reboot and you thing that it should do it in 2 minutes, the 5 minutes it may take to reboot is real long and lonely.
Physical drive sizes, nice to know what should have been there.
Virtual drive sizes, again nice to know what should be there.
A set of Server XXX or whatever is your flavour disks, nothing like trying to rebuild a server when all you have is a XP Service Pack CD.
As a friend of mine calls it, a lifeboat machine. You need another box to run your VM's on if your main box crashes, I mean after all, isn't this part of the reason we are here...
Notes on the complete build, what did and did not go right. What programs are installed on each VM. This is real important if you have to rebuild a VM that did something...but what was it... Belarc will give you a nice report of all installed software.
All of this stored somewhere else other than on a VM or the Host machine. A printout is good, a CD is good, but whatever works for you.
A VM toolkit. start looking at some of the VM or VHD tools out there and see what can or cannot help you if a VHD disk gets corrupted.
Belarc - nice report on a server, hardware software etc.
VM Back - Driver Disk to open a VHD
WinImage - a program to allow you take a look at the data on a VHD
Hope this is of some use.