[virt-tools-list] live-migrating a VM whose current host's storage is fubar'ed

[Cole Robinson]

On 04/15/2014 05:16 PM, Digimer wrote:
> Hi all,
> 
>   For those on the linux-cluster list, this is a similar question to my
> post[1] there.
> 
>   I recently had a client destroy their node's RAID array (they yanked hard
> drives until the array was destroyed). The VMs running on the node continued
> to operate for another hour, impressively. Their storage was based on DRBD, so
> the VM's storage just started going to/from the other node's storage.
> 
>   The problem was when I tried to migrate them off of the damaged node to a
> healthy node. Without being able to write to the logs (I assume), the
> migration failed. In the end, I had to force-off the damaged host and reboot
> the VMs on the backup node. This caused an outage which, I think, could have
> been avoided.
> 
>   So my question is; Can VMs be migrated if/when the host's FS is
> read-only/destroyed? If so, how?
> 
> Thanks!
> 
> 1. https://www.redhat.com/archives/linux-cluster/2014-April/msg00010.html
> 

Probably a better question for libvirt lists, CCd, but I don't think anyone
tests a scenario like that so there's bound to be problems.

- Cole