Thursday, September 17, 2009

HyperV networking works on Server 2008 R2 guest but not Server 2008 guest

The Scenario:

Hyper-V R2 (Server 2008 R2) host, Server 2008 guest (not R2), Server 2008 R2 guest

The situation plays out like this:

I create a VM and install Server 2008 R2 Standard.

The external network, connecting me to the internet, works fine and the guest OS automatically has a working network device and connection.

I shut down this VM and leave it off.

I then create another VM, exactly the same, choosing the same external network as above. This time I install Server 2008 Standard (non-R2).

The server does not find its network card, and therefore cannot connect to the internet. When I look at the guest OS, there is a yellow splat in the device manager for the virtual network adapter.

 

My first question in response to this:

Did you install the Integration Components within the VM?

 

Here is why:
Server 2008 has the ICs built in to the OS (they are extremely similar to device drivers).

But, versioning issues can come into play - the host and guest must match for optimum performance.

With the release of R2 the ICs included backward compatibility - thus allowing an R2 VM to 'just work' when you install it onto a Hyper-V v1 (2008, but not 2008 R2) host.

Now, when you have a Server 2008 VM on an R2 host - the VM built-in ICs are older than the host ICs - thus the ICs in the VM need to be updated.

Using the Hyper-V manager Console, open the console of the VM and choose Action, Install Integration Services - then respond to any prompts.

Thank you “Kelly AZ” for describing this problem so well in the TechNet forum.

http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/c08e2f66-802b-43b0-aa9c-589695c31678/

2 comments:

Arian said...

Hi

I have Windows Server 2008 non R2 with HyperV.
In the HyperV I have Win7 installed.
On the Event Logs I get this error:

"Device 'VMBus' in 'Win7' cannot load because it is incompatible with virtualization stack. Server version 13 Client version 65537 (Virtual machine D6D7F94F-A9E8-40FF-A98D-5B3C087AB5BE)."

Source: Hyper-V-Worker
Event ID: 23012
Level: Error


I have read your post. Isn't it possible to update the VMBus on the Hostmachine to the version of which it has Win7?
Or have I to downgrade the version of Win7 to this on W2K8 non R2?

Have you any idea how to fix it?

Cheers
HugePan

BrianEh said...

You are essentially running an R2 guest on a v1 host.

A songle componenet of hte hypervisor cannot be upgraded, only the entire thing.

The solutions are:
- downgrade the ICs in the guest.
- upgrade to Hyper-V R2

MSFT would like you to upgrade to R2, for many reasons, not money.

Personally, I agree, upgrade to R2 - there are many things that are improved.