[libvirt-users] Migrating guests

[Dominique Ramaekers]

Hi,

I'm experimenting with the migration function of virsh. I'm doing the migrate with following commands:

virsh migrate --life --persistent --copy-storage-all --verbose --abort-on-error domain qemu+ssh://root@destination/system
virsh migrate-setmaxdowntime domain 20000

However sometimes at the end of the migration, the guest isn't started on the destination host. So I'm left with a machine that had an improper shutdown...

If a live migration isn't reliable, I'm thinking to migrate as such:
- guest is still runing
- copy or rsync the disk image to the destination
- shut down the guest
- rsync the disk image again (to minimise the off-line period)
- dumpxml of guest and copy to destination
- define and start the guest on the destination

With the methode of the live migration, the machine will be unresponsive for max 20s = 20000ms (or less if I chose to). The migration it self will take op to 5 hours but I guess I plan these nightly.

With the other migration the guest will be really off-line for the duration of the (second) rsync. In my case with disk images from 50 to 150Gb, the rsync wil take up at least 30 minutes and every connection will be closed...

Does any body has good experiences with live migrations (without shared storage)? Any tips?

Any thoughts on the second method of migrating?

Greetings,

Dominique.