We have a few "servers" (really workstation PC's acting as servers) sitting around doing some small tasks. I have a spare server (Older Compaq ML380, 2x 900 Mhz, 2GB RAM, 3x 74GB HDD in RAID 5) and I decided to play around with Virtual Server to get these small sudo servers off of the workstations and onto a real box.

I have setup Virtual Server 2005 (Very Easy) and configured a base Windows 2003 install. My question is how should I set the virtual hard drives up? I have read a little bit about undo disks but I am not sure if that would allow me to use this base image for all the virtual machines and have the virtual machines just create a single undo file for each virtual server.

Should I just copy that base virtual hard drive to a different location and rename it? Also, what is the difference between a virtual SCSI hard drive and a virtual IDE hard drive other then the size limits?

I never personally use "undo disks". I wouldn't use it on a real (non virtualised) server, so I've never seen a reason to use it.

As for the drive differences:

SCSI will be slightly slower in performance than IDE.
More guest operating systems will have drivers built in for the IDE drive, some operating systems may need extra configuration with SCSI ones.
I think IDE allows the use of 4 or 8 disks, while SCSI allows the use of 24/28 disks (may have to confirm that one though).

In the past I have copied Xen images not too sure on VS. If you manage to copy the image, make sure you don't boot it up as the same time as the other image though (hostname, IP conflicts etc.). You should also change the SID. Theres a tool to do it from sysinternals.

You should use SCSI over IDE since the drivers for the virtual SCSI drives are optimised.

This should answer it:

"Contrary to common sense, the performance of our emulated SCSI controller is slower than that of our emulated IDE controller. The reason for this is that the SCSI controller is a lot more complicated to emulate than the IDE controller. Now - this changes once you have Virtual Machine Additions installed. As part of Virtual Machine Additions we install an accelerated SCSI driver. Once this driver is installed the performance of our emulated SCSI controller is significantly faster than our emulated IDE controller."
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