[libvirt] Live migration woes

[Thomas Treutner]

On Monday 08 February 2010 20:22:44 Lance Albertson wrote:
> > On Fri, Feb 05, 2010 at 03:21:32PM -0500, Thomas Sjolshagen wrote:
> >>> is anyone using libvirt-git and qemu-kvm post-0.11 and can live
> >>> migrate VMs successfully for- and backwards? qemu-kvm-0.11 seems
> >>> to be the latest release were live migration works, and I'm
> >>> trying to figure out if its a kvm or libvirt problem, since there
> >>> were other things (balloon parameter f.e.) that were changed with
> >>> qemu-kvm-0.12 and caused troubles when using libvirt.
> >>
> >> Yes.
> >>
> >> I'm using the virt-preview repo (rawhide) and I just noticed,
> >> today, after re-upgrading to 0.12.2-5 (since -4 has a rather nasty
> >> IO problem for virtio devices against raw image files) that my
> >> live-migrations fail with the following error message on the
> >> destination system (i.e. the system the I'm trying to migrate to):
> >>
> >> /var/log/libvirt/qemu/<guest>.log: Unknown savevm section
> >> -2038417646 load of migration failed
> >
> > This looks like a new QEMU bug to me
>
> I can confirm this bug is happening on Ganeti as well [1]. It appears
> that if you sync the time on the guest VM before migrating back to the
> other node it will "succeed" most of the time. Has anyone opened a bug
> for this on the qemu-kvm bug tracker yet? I was about to do that myself.

Using acpi_pm as clocksource on both guests and hosts seems to fix it for now. 
(For guests, clocksource=acpi_pm on kernel cmdline)


-t