migration between clusters fails: no matching import/export format found for storage

[CRCinAU]

Trying to migrate a VM from a standalone PVE system to a 2 node clustered PVE system.

When I start the migration, it fails quickly with:

2025-07-03 14:51:09 remote: started tunnel worker 'UPID:mel-pm1:00270FB2:07501C9E:68660C3D:qmtunnel:205:root@pam!pdm-admin:'tunnel: -> sending command "version" to remotetunnel: <- got reply
2025-07-03 14:51:10 local WS tunnel version: 2
2025-07-03 14:51:10 remote WS tunnel version: 2
2025-07-03 14:51:10 minimum required WS tunnel version: 2
websocket tunnel started
2025-07-03 14:51:10 starting migration of VM 202 to node 'mel-pm1' (mel-pm1)
tunnel: -> sending command "bwlimit" to remote
tunnel: <- got reply
2025-07-03 14:51:10 found local disk 'vm-storage:vm-202-disk-0' (attached)
2025-07-03 14:51:10 copying local disk images
tunnel: -> sending command "disk-import" to remote
tunnel: <- got reply
2025-07-03 14:51:10 ERROR: error - tunnel command '{"format":"raw","with_snapshots":0,"allow_rename":"1","migration_snapshot":0,"storage":"nvme-zfs","cmd":"disk-import","volname":"vm-205-disk-0","export_formats":"raw+size"}' failed - failed to handle 'disk-import' command - no matching import/export format found for storage 'nvme-zfs'
2025-07-03 14:51:10 aborting phase 1 - cleanup resources
tunnel: -> sending command "quit" to remote
tunnel: <- got reply
2025-07-03 14:51:11 ERROR: migration aborted (duration 00:00:02): error - tunnel command '{"format":"raw","with_snapshots":0,"allow_rename":"1","migration_snapshot":0,"storage":"nvme-zfs","cmd":"disk-import","volname":"vm-205-disk-0","export_formats":"raw+size"}' failed - failed to handle 'disk-import' command - no matching import/export format found for storage 'nvme-zfs'
TASK ERROR: migration aborted

In this scenario, the source side is LVM, the target side is ZFS.

 

[fabian]

yes, this is currently a limitation for offline/storage-only migrations, the ZFS plugin only accepts volumes exported from ZFS. you can use a live migration instead, which should support this particular storage combination

https://bugzilla.proxmox.com/show_bug.cgi?id=6087 tracks this issue, I don't think there are any technical blockers (at least for migrations not involving snapshots), just needs somebody implementing it.

 

[CRCinAU]

Thanks @fabian - I didn't think of trying a live migration - as the systems are in two very different locations and network configs are completely different for the VM.

I ended up doing a backup to local storage, then scp'ing it between systems and doing a restore on the target. It's kind of fun migrating stuff between my home lab and a colo box - just for fun

 

[fabian]

yes, live migration of disks currently in use by the VM happens within QEMU using a mirror job, so the volume format outside doesn't matter as the contents are copied from the guest point of view anyway.