I have ubuntu 18.04 host with 18.04 containers. They’ve all been running for a while and was upgraded from 16.04. I had an old lxd 2 something from ppa.
Tried to do a long over due migration to snap:
=> Connecting to source server
=> Connecting to destination server
=> Running sanity checks
=== Source server
LXD version: 3.0.3
LXD PID: 14775
Storage pools: 1
=== Destination server
LXD version: 3.9
LXD PID: 4912
Storage pools: 0
The migration process will shut down all your containers then move your data to the destination LXD.
Once the data is moved, the destination LXD will start and apply any needed updates.
And finally your containers will be brought back to their previous state, completing the migration.
Are you ready to proceed (yes/no) [default=no]? yes
=> Shutting down the source LXD
=> Stopping the source LXD units
=> Stopping the destination LXD unit
=> Unmounting source LXD paths
=> Unmounting destination LXD paths
=> Wiping destination LXD clean
=> Backing up the database
=> Moving the data
=> Updating the storage backends
error: Failed to update the storage pools: Failed to run: zfs set mountpoint=18.04 nas/vms/containers/dns@snapshot-pre: cannot open ‘nas/vms/containers/dns@snapshot-pre’: dataset does not exist
Seems to me it tried to mount a snapshot (with space in the name) rather than a file system.