CHKDSK always runs on Hyper-V image

If you don't plan on using the host OS to run anything but Hyper-V, I don't think putting VMs on the same partition as the OS is going to matter much. I'm using Hyper-V on a couple workstations with 10k rpm disks with the OS on one and VMs on both and I don't notice a difference in VM performance between them.

You can eat up disk very rapidly with VMs, so its worth having a big & slower disk for archives & backups (maybe not necessary if you have good network storage and a fast network).

If you are building it yourself and want to stay within a reasonable budget, I'd suggest 4-6x 10 rpm disks in raid 10 (300 GB disks can be had for ~$200 each on NewEgg). Then maybe 2x 1-2TB disks in raid 1 (if you add this, you might as well put the OS on it).

Using dynamically expanding disks and snapshots both adversely affect performance (for virtualizing a workstation it's fine, for a server maybe not). And for any disk intensive service, I'd use direct access to the service's backing store (e.g., database or file-server). If you move the I/O bottleneck off the virtual OS partition, you can probably snapshot the virtual server OS without worrying about performance.

Finally - you may want more than 8GB (Hyper-V can't share unallocated RAM, and the host needs some, too) - but that depends on how intensely they will be used.

I hope this is useful. And if you do some experimentation and benchmarking, I think many people would be interested to see the results. As you've probably noticed, there is a paucity of performance data in this area.

Are you restricted to Hyper-V as the Hypervisor?

However the Hyper-V Planning and Deployment Guide and Hyper-V: Using Hyper-V and Failover Clustering is probably what you are after as a starting reference.

I haven't used Hyper-v but based on what I have read and use of VMware ESX what you are proposing shouldn't be a problem at all. FC or iSCSI shouldn't matter provided you have setup the base Storage, and Microsoft Clustering for Hyper-V properly. Probably best to go through the Microsoft documents and consider rebuilding your setup again if needed.

Have you got any information for configuring your SAN for use with Hyper-V from your SAN Vendor?