[CentOS] CentOS 5.6 and KVM failure

Thu Apr 21 18:16:07 UTC 2011
Kenni Lund <kenni at kelu.dk>

2011/4/21 Ian Forde <ianforde at gmail.com>:
> Turns out that wasn't the only problem I faced in my migration.  With 2
> KVM servers, both sharing a volume mounted via NFS for VMs, I migrated
> all VMs to the second node, upgraded the first, them moved them all back
> to KVM1.  Instant disk corruption on all VMs.  Boom.

Are you sure it was the migration and not the raw/qcow2 error which
caused the disk corruption?

I just had two Windows Servers with image corruption after upgrading
from 5.5 to 5.6 and booting the first time with the raw setting,
before changing it to qcow2 :-/

These two images were both on the same host, which is plain CentOS 5
*BUT* with a 2.6.37 kernel (and therefore 2.6.37 KVM module) from

It could be my special case of running with a vanilla KVM-module +
CentOS KVM userspace which allows the corruption to happen, but if
other people are seeing disk corruption with the regular
kernel/kmod-kvm, then this "known issue" should probably have a big
fat red warning in the release notes..

Best regards