[CentOS-virt] win2008r2 update on centos 6 host made system unbootable

Wed Dec 9 00:00:28 UTC 2015
Dennis Jacobfeuerborn <dennisml at conversis.de>

On 09.12.2015 00:39, NightLightHosts Admin wrote:
> On Tue, Dec 8, 2015 at 5:26 PM, Dennis Jacobfeuerborn
> <dennisml at conversis.de> wrote:
>> Hi,
>> today we ran into a strange problem: When performing a regular Windows
>> 2008r2 update apparently among other things the following was installed:
>> "SUSE - Storage Controller - SUSE Block Driver for Windows"
>>
>> Previously the disk drive was using the Red Hat virtio drivers which
>> worked just fine but after the reboot after the update I just get a blue
>> screen indicating that Windows cannot find a boot device.
>>
>> Does anyone understand what is going on here? Why is the windows update
>> installing a Suse driver that overrides the Red Hat driver even though
>> it is apparently incompatible with the system?
>>
>> Regards,
>>   Dennis
> 
> Did you roll back the driver and did it work after that?

I can't roll back the driver for that device because I can't boot the
system. The only way I can boot into the system is by changing the disk
type to IDE but then I cannot roll back the driver because the entire
device changed. As far as I can tell the Suse version of the virtio
block driver is incompatible with the incompatible with the system but
right now I see no way to tell windows "Uninstall the driver completely
for the entire system" so that on the next boot it would fall back to
the old virtio driver from Red Hat.
I tried installing the current stable drivers from this URL:
https://fedoraproject.org/wiki/Windows_Virtio_Drivers

But Windows refuses and says the driver is already up-to-date.

What worries me is that I want to update other win2008r2 guests as well
but now fear that they will all be rendered unbootable by such an update.

Regards,
  Dennis