Unable to Delete Dataset - "Dataset is Busy" Error with qbittorrent-nox

Hello TrueNAS Community,

I’m encountering a persistent issue with my TrueNAS installation (ElectricEel-24.10.2) where I’m unable to delete the dataset “tank/iso”. When I attempt to delete it through the web interface, I receive the error: “[EBUSY] Failed to delete dataset: cannot destroy ‘tank/iso’: dataset is busy. These running processes are using tank/iso: qbittorrent-nox”.

However, I’ve taken several steps to investigate and resolve this, but the issue persists:

  1. Checked Active Processes: I’ve used the TrueNAS web interface and the command ps aux | grep qbittorrent-nox via SSH to check for running qbittorrent-nox processes. While I did find processes initially, they seem to reappear very quickly after being killed.
  2. Attempted to Stop qbittorrent-nox Service: I tried to stop the qbittorrent-nox service, stopped completely the docker container and gluetun too (I’ve installed them via dockge). seem anyway that qbittorrent.nox is referred to an old installation (I used the infamous and crappy truecharts…)
  3. Tried to Prevent Restarts: I attempted to disable the automatic start of the qbittorrent-nox . I also tried terminal commands like kill on the qbittorrent-nox processes and investigated s6-supervise (the parent process) and tried to kill those as well, but the qbittorrent-nox processes keep restarting.
  4. Rebooted the System: I rebooted the entire TrueNAS system and immediately tried to delete the dataset after the system came back online, but the “dataset is busy” error persists.
  5. Checked Mount Points: I used the command mount | grep tank/iso to ensure the dataset wasn’t mounted. The command returned no output.
  6. Checked ZFS Holds: I ran zfs holds tank/iso to check for any active ZFS holds on the dataset. The output indicated “no datasets available”, suggesting no holds are present.

Despite these steps, I am still unable to delete the “tank/iso” dataset due to the “dataset is busy” error, seemingly caused by qbittorrent-nox which keeps restarting or having some persistent lock.

Has anyone else experienced a similar issue or have any suggestions on how to further troubleshoot this? I’m open to any advice or commands I can run to gather more information or resolve this.

Thank you in advance for your help!

I’ve “resolved” thanks to deepseek R1…

sudo zfs set mountpoint=none tank/iso

sudo zfs destroy -fvr tank/iso

but still need to eliminate the zombie process…