As you may know, all newer hard drives are being shipped with 4k sector sizes. If you would like more detail on this, please see http://www.bit-tech.net/hardware/storage/2010/04/01/the-facts-4k-advanced-format-hard-disks/1
I recently purchased one of the new Western Digital 3TB USB drives for use on one of my DPM servers, which is a Hyper-V guest. Unfortunately, when I started to try to use the disk, Hyper-V refused to create new VHD files on the disk, or to boot VHD files that were manually copied to the disk. All other functions seemed fine.
After trying a multitude of formatting and partitioning options and speaking with a couple of higher-ups at Western Digital, I realized there was a fundamental incompatibility between Hyper-V and 4k physical sectors. I was planning to return the drive, but got caught up in some other projects and got back to this project yesterday to find a new KB article that seems to have been pulled – but thanks to google cache it’s still readable: http://support.microsoft.com/kb/2515143
It references not only the root problem but a hotfix (that is also included in the recently released Service Pack 1 for Win2008R2): http://support.microsoft.com/kb/982018
I decided to download and try the hotfix on a non-production Hyper-V server. Here is what you get when using an advanced format disk on Windows 2008 R2 RTM Hyper-V:
And following the patch and reboot I now get…
…the exact same error. Sad face. Creating the VHD elsewhere and copying it over still doesn’t work either as Hyper-V still squawks about compatibility; looks like MS has more work to do:
UPDATE 4/18/2011: As you can see from my above edit, there is a new KB article specifically addressing this issue WRT hyper-v – and the bottom line is you cannot put VHDs on native 4k sector disks (and disks with 512b emulation will take a performance hit)… bummer!
