Virtio Drivers on Domain Controller

Hello All,

I haven’t been able to find a decent source for best practices in this situation.

I’ve been using KVM on CentOS for a while with great success. I’m beginning to support SBS 2011 installs virtualized in KVM on CentOS 6.

SBS or other Windows Active Directory/Domain controllers don’t support enabling write caching on the OS drive.

If I use the virtio driver for the hard drive, write cache is enabled by default and I can’t turn it off, this is followed by Windows complaining about write caching being enabled. If I switch back to IDE then write cache is off as it should be.

I’d like the benefit of using the virtio driver but without having write cache enabled.

Has anyone else run into this or have a recommendation?

I am currently using IDE for the OS portion and a virtio HDD for the data portion (where Exchange and folder redirects have been moved to).

Thanks!