Filesystem errors with VirtIO

[John Nielsen]

On Jan 20, 2014, at 8:39 AM, Philipp <mailinglists at cypresscreek.de> wrote:

> I'm running FreeBSD 10.0-RELEASE on a virtualized KVM server. I'm
> using VirtIO from base to access NIC and HDD directly. Filesystem is
> UFS2 with Journaling and SU. Last week I had to reinstall FreeBSD
> because the salvation of the several filesystem errors wasn't possible
> anymore. I don't have any evidence but I guess it has something to do
> with the VirtIO driver.
> 
> After running the machine for 48 hours with a freshly installed
> FreeBSD 10 several soft update inconsistencies occur:
> [fsck output trimmed]
> 
> After a reboot different inconsistencies appear. I had the very same
> problems with 9.2-RELEASE, which caused the need of a reinstallation
> of the OS (errors like "vtbd0: hard error cmd=write fsbn 24162"
> occured).
> 
> Can someone confirm these problems with VirtIO? What else can I do?

FWIW I've been running multiple FreeBSD VMs atop KVM+virtio for some time and haven't seen any issues like this. My VMs include FreeBSD 9.2 and 10.0-RC on both UFS and ZFS.

What can you tell us about the underlying storage? LVM volume? iSCSI? Qcow2 or other disk image file? If so, what type of filesystem is it on? etc.

JN