Thursday 6 February 2014

Hypervisor not running (3112) - AMD FX series CPUs "Virtual machine could not start because the hypervisor is not running"

Having recently decided to build a new test machine for virtual activities, I decided on a budget FX-6300 (piledriver) with a Gigabyte board and 32GB of corsair memory.

After installing Server 2008 R2 and adding the hyper-v role, my first problem started with hyper-v not being able to mount the VHD files.

No worries there, that's a known problem and needs 2008 R2 SP1 installing.

After installing SP1, I ran into a new problem where I got the following error message:

"Hypervisor not running" error 3112

Lots of digging later and i'd managed to get myself into a panic; I was thoroughly convinced i'd wasted my money on a system that wasn't going to run Hyper-V. I'd checked all the basics, AMD Virtualisation support etc and was looking at other peoples suggestions such as hardware DEP.

After much searching, I stumbled on an Microsoft KB support article (2568088) which cured issues with hyper-v and the bulldozer CPUs. In desperation, I tried installing it on the off chance that it would solve my problem even though I have a piledriver.

And guess what? It did.

Thank you Microsoft for the hot-fix, perhaps its about time you updated the details to include other architectures?

I hope that certainly hopes somewhere out there as much as it helped me - KB article is below:

http://support.microsoft.com/kb/2568088

Edit: 10/04/2015
Looks like the hotfix details have been updated now to reflect that it started with the bulldozer series.

Update: 16/07/2015
This problem occurred today on a server following a RAID failure - the secondary plex kicked it and the virtual machines wouldn't start. Long story short, the hypervisor wasn't starting automatically. to fix, I can this from an elevated command prompt:

BCDEDIT /set hypervisorlaunchtype auto   

On a side note, it's also come to my attention that work-arounds have been added to the hotfix notes to get around the AMD issues:

To work around Issue 1, follow these steps:
  1. Start Hyper-V Manager.
  2. Right-click the virtual machine in question, and then click Settings.
  3. Under the Processor configuration for the virtual machine, click to select the Migrate to a physical computer with a different processor version check box, and then click OK.
  4. Start the virtual machine.