DCs on VMWare Server guests

[Norphy]

Bit of history:

We have a three domain, single forest setup. We have two DCs for each domain. One of the root DCs failed just recently and has been replaced.

It's a fairly meaty server, pair of 2GHz Opterons and 2GB of RAM. This has got me thinking: The secondary DCs for the other two domains are running on old hardware. Instead of replacing them, why not install Linux and VMWare Server on the new server (I'd prefer to use Xen but these Opterons don't support hardware virtualisation so I wouldn't be able to run Windows on the Xen guests) and run all three secondary DCs as guests?

They wouldn't be used for anything else, just as DCs. Licensing shouldn't be an issue as Windows Server Enterprise allows for up to five virtual installations on a single license and we can re-use our existing CALs once the physical servers are decommissioned.

My only concern would be performance. I've noticed that network throughput on a VMWare guest is not especially high and I should imagine that would be the same for disk throughput too.

Does anyone have any thoughts? Have they tried this? How well has it worked?

[DMcCoy]

3 DCs, one box. What happens if it dies?

[Norphy]

Then we replace the box. They'd only be secondary DCs, the network would still run. If anything, this scenario would be a little easier to recover from assuming the hard drive hosting the images doesn't die. It would just be a matter of sticking VMWare on another box, putting in the hard drive with the images on and everything is back up and running again.

[DMcCoy]

Oh yes, missed that bit while patching a windows box :P

DCs aren't very high utilisation, so performance should be ok.