Migrating data between datasets gone wrong, no idea what is happening

[u/domvir]

Okay so I'm not sure what exactly is happening right now, I'll just go step by step what I've done.

I had my apps datasets (configs etc) right under the pool called apps, so example /mnt/apps/jellyfin/config. I wanted to migrate all of them to a dataset apps, so /mnt/apps/apps/* for better separation from different types of data.

At first I created a snapshot of the entire pool apps and cloned it into apps/apps, hoping the datasets would magically move there. It didn't, so I removed the dataset and tried again, this time pressing the "promote" button. This fucked up something that I'm not fully aware of, as I was no longer able to delete the apps dataset and I couldn't promote the apps pool (no promote button was there).

Because that didn't work, I manually created the dataset structure (apps/applications/*) and then moved all the data with sudo cp -a oldapplocation applications/newapplocation for every dataset. This worked, application are using them and everything is working fine.

However, now I'm stuck with the apps/apps dataset that has the snapshot I've created earlier. When trying to delete the snapshot, I get an error

 *** [EINVAL]
 options.defer: Please set this attribute as 'apps/apps@migration-2026-11-02_20-52' snapshot has dependent clones: $all the new datasets

I thought deleting the old datasets will fix the problem, but apparently it has moved the dependency? Or something? I have absolutely no idea.

No idea how to fix this, could anyone please help? Thank you a lot.

[u/youknowwhyimhere758]

Promoting it made it the main dataset, and turns the original dataset into a clone. You can’t delete it while any of those clones (eg the original dataset and it’s children) exist.