Online / Live Migration with ZFS-Replicated local VMs?

n1nj4888

Well-Known Member
Jan 13, 2019
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Hi There,

Is there a technical reason why Online / Live Migration of VMs that are replicated across local disks (from Node 1 local-zfs to Node 2 local-zfs) does not currently seem to be permitted? If this is not currently permitted / available, is it planned to be made available in Proxmox 6 Final or the future?

My understanding is that ZFS replication of VMs is there to enable a quick spin up a replicated VM on Node 2 should Node 1 go down (via HA only currently?) ... but Online / Live Migration of replicated VM to Node 2 would also be great in case of planned work on Node 1... In this case, presumably the Online / Live Migration should just replicate the delta since last scheduled replication and move the VM to Node 2?

Thanks!
 
the technical reason is that to live migrate with a local disk, we have to do a qemu drive-mirror to an nbd server on the target
this does not work currently with a snapshot as base afaik and definitely cannot use a zfs send/receive instead
what could work (but no one works on this currently) is some kind of 'pause vm; replicate; live migrate in paused state; start on the target' but this would have some down time depending on the delta/network/etc.

what works already is to shutdown, offline migrate (only the delta will be sent), and start on the target node
 
Thanks for the detailed response!

what could work (but no one works on this currently) is some kind of 'pause vm; replicate; live migrate in paused state; start on the target' but this would have some down time depending on the delta/network/etc.

This sounds like a good alternative. If this is not being worked on currently, should I raise it as a bug/feature request through bugzilla?

Thanks!