On Fri, Apr 15, 2022 at 16:58:08 +0200, Valentijn Sessink wrote:
Hi list,
I'm trying to migrate a few qemu virtual machines between two 1G ethernet connected hosts, with local storage only. I got endless "error: operation failed: migration of disk vda failed: Input/output error" errors and thought: something wrong with settings.
However, then, suddenly: I succeeded without changing anything. And, hey: while ! time virsh migrate --live --persistent --undefinesource --copy-storage-all ubuntu20.04 qemu+ssh://duikboot/system; do a=$(( $a + 1 )); echo $a; done
... retried 8 times, but then: success. This smells like a race condition, doesn't it? A bit weird is the fact that the migration seems to succeed every time while copying from revolving disks to SSD; but the other way around has this Input/output error.
There are some messages in /var/log/syslog, but not at the time of the failure, and no disk errors. These disks are LVM2 volumes and they live on raid arrays - and/so there is not a real, as in physical, I/O-error.
Source system has SSD's, target system has regular disks.
1) is this the right mailing list? I'm not 100% sure. 2) how can I research this further? Spending hours on a "while / then" loop to try and retry live migration looks like a dull job for my poor computers ;-)
It would be helpful if you provide the VM XML file to see how your disks are configured and the debug log file when the bug reproduces: https://www.libvirt.org/kbase/debuglogs.html#less-verbose-logging-for-qemu-v... Without that my only hunch would be that you ran out of disk space on the destination which caused the I/O error.