Firstly, go and read this article:
It discusses the merits of defragmenting SAN based disks. With the heavy usage of SANs within the VM sphere, it makes it particularly relevant.
OK, done reading? I’ll continue…
After deploying a new VM yesterday, from one of our Windows 2008 R2 64bit templates, I noticed the new Task Scheduler. I was having a bit of a poke around and noticed that by default there was a scheduled task to defrag all its “local” disks at 1am Wednesday every week. Now this task is disabled, but be careful about enabling this in your gold template.
Besides your personally thoughts on the need to defrag SAN disks, imagine all your VMs running on a SAN decide to defrag all their disks at the same time. Yikes! Hopefully Microsoft put in randomization on the day and time during the night these things are set, when the OS first installs or during sysprep. However it doesn’t appear so.