Reassigning a vm-disk (zfs) from a guest to another guest


New Member
Jun 9, 2023
Hi there !

I have a goal of moving one of my vm-disk that is in my zfs pool to another guest vm. They are both ubuntu machine.
I read online that it could be as simple as using the "reassign owner" button in the GUI, but I wanted to make sure because this is an important disk.
Also, it is difficult for me to make a backup of this disk since it's around 6-7TB. Backups for vm are done weekly tho.

I wanted to know if there is any details that I should be looking for before making the move.
The source vm is seaBIOS and the destination vm has a UEFI bios (see attached pictures). The only reason why I'm switching is because I need the UEFI for GPU passthrough.



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Reassigning an owner in PVE will just rename the disk (e.g. zfs-pool:vm-100-disk-0 to zfs-pool:vm-106-disk-1, where the last number might change depending on availability) and move its configuration to the target guest accordingly.

What kind of data is in the disk? If there is nothing specific to the source guest, e.g. a boot partition, it should work.
I don't think that there is any guest dependent information. This VM contain my media server with a lot of docker, but almost every config files and data files is in the disk. So there is almost no config for me to change but the ip address when rebooting all the applications.

But thanks for the help, I was overthinking it. I may try to test it with test-vm-disk on both sides.


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