We've got a Dell R710 running Server 2012 with Hyper-V that had two disks go bad last week. Luckily we run RAID 6, so it just needed a rebuild after the drives were replaced.
This server runs a fileserver inside a VM. The VM will no longer boot after the rebuild. It runs the "Hyper-V Please Wait..." screen, then just stops with a black screen. I tried pinging the IP address of the VM but it's unreachable, so it doesn't seem to simply be a display error.
I tried creating a second VM using the same parameters, with the VHDX file as the disk, but it still wouldn't boot. So I mounted the Server 2012 DVD ISO to the VM so I could run the recovery environment and try some repairs:
sfc /scannow /offbootdir=C:\ /offwindir=C:\windows - says that it can't repair some of the corrupted files.
DISM /image:C:\ /cleanup-image /restorehealth - seemed to work ok, no warnings or errors.
chkdsk /f C: - took almost two days (the VM is 8TB and has millions of tiny files), and said it fixed a number of errors.
Unfortunately, none of those fixed the issue, and the VM still doesn't boot. I looked in Event Viewer at all the Hyper-V logs, but there are no related warnings or errors to help me further diagnose.
I'm now restoring a backup of the VM, hopefully that backup will boot properly.The restore operation will take a while due to the size of the VHDX, so while I'm waiting I figured I'd ask if there's anything else I can try.
Thanks!