My 2012 R2 Server is running on 5 RAID6 HDDs + 1 spare (WD REDs). It's used as a storage server, with two Windows 8.1 Pro Hyper-V clients. The problem is that the disk access in general is kind of slow. So my idea is to move the windows to RAID1 SSD, and move both Hyper-V clients to another RAID1 SSD, and keep RAID6 HDDs just for users files storage.

Both Hyper-V setup as dynamic disk files. Is there a way to convert them and run them as direct disk access from SSD divided into two partitions?

Thanks so much for any help.

• Edited by Dima3425 Wednesday, December 17, 2014 5:07 AM

Hi!

A vhd file can not be converted into actual physical storage using Hyper-V tools. Neither does Hyper-V use physical partitions, but rather the entire disk if you wan't your VMs to access physical storage directly.

You need to bring your SSD disks offline in the Hyper-V host disk manager, so that Hyper-V can present the disks to virtual Machines. This is called a "pass-through" disk.

Then you need to migrate the contents from the vhd file on to the physical disk used in the VM. You can attach a vhd in the hosts disk manager, or mount both disks to the VM and clone the contents from the vhd on to the pass-through disk using an imaging software such as Ghost.

• Marked as answer by Elton_JiMicrosoft contingent staff, Moderator Tuesday, December 23, 2014 4:52 AM

Only a full disk / LUN can be presented to a VM as a passthrough, not a partition.

I am actually curious as to why you feel that taking the VMs out of a VHD would be a significant performance increase?

My personal opinion is that your performance has nothing to do with the use of a VHD, as it has been proved by MSFT that VHD performance (since 2012) has been near native (better in rare cases with caching) than native disk performance.

You will gain a lot simply from breaking your one big RAID as you describe than you will with making any other changes.

Thanks. I'll experiment as soon as I get the SSDs.

• Edited by Dima3425 Wednesday, December 17, 2014 6:37 PM

Hi Dima3425,

I would like to check if you need further assistance .

Best Regards,

Elton JI

I ended up moving Server OS to a RAID1 Intel SSD, two VMs VHDs to a 2nd RAID1 SSDs, and user storage files on a 6x RAID6 HDDs. Everything works great and super fast.