Hey There,
I just went through this same issue. The key for me was to ask ChatGPT how to do this from the command line using the “incus” tools as this is what drives the Instances tool in TrueNAS.
It was all pretty straight forward in the end:
# 1) Stop the VM so the volume isn’t in use
incus stop freepbx-muko
# 2) Copy the live block data into RAID10
incus storage volume copy nvme-pool/freePBX RAID10/freePBX --volume-only
# 3) Verify the new volume exists
incus storage volume list RAID10 | grep freePBX
# 4) Re-point your VM’s disk0 at the RAID10 copy
incus config device set freepbx-muko disk0 pool RAID10
# 5) Start the VM again
incus start freepbx-muko
# 6) Once you confirm the VM is working off RAID10/freePBX, delete the old copy
incus storage volume delete nvme-pool freePBX
Honestly in this whole process I just copied and pasted any errors into chatGPT and it went and found the reasons why and fixed them. Absolute time saver as there is very little documentation I could find that fitted this exact scenario.
Hope it helps for next time rather than using “clonzilla” which is still a good workaround!