Two zfs pools with same mountpoint problem

[ddcSupport]

I attached an external USB drive to make backups of another pool. I used the GUI to create a single disk pool named Backup, and it mounted on /Pool where there is already a zpool. Now I cannot unmount or manipulate Backup in any way because the system responds "cannot unmount '/Pool': pool or dataset is busy" to every command... "zfs set mountpoint" for example.

I've removed the storage from the cluster without incident, but cannot figure out how to change or remove the Backup zpool. I'd rather not reboot the storage node. Running 7.4 if that's relevant. Thanks in advance.

 

[Sviat]

Hi,
It looks like your Backup pool mounted on the same /Pool path as an existing zpool, so it could be fixed by exporting Backup and re‑importing it with a different mountpoint then destroying it if it not needed.