Just a quick one this (I hope) as I can't seem to dredge up anything with my googlenet that directly answers my question.

I have a fibre channel SAN, two virtual hosts and a physical host that will run VMM2k8. I want to use Clustered Shared Volumes for high availability and PRO etc. so I can have one big LUN for all my VMs. I need another little LUN to be witness disk.

Now for purposes of speed, VMM's library share is best hosted on the SAN (as confirmed by some googling, "it is a best practice to have a library server on the same SAN as the virtual machine hosts that use the library server") but a CSV volume can only be used successfully by Hyper-V (source).

So, to clarify - do I need to create a separate LUN for the library share, accessible by all hosts? If so, how big does it need to be - is it just storing VM templates for quick provisioning of new servers? I'm only looking at around a dozen virtual servers tops here.