Unwanted Snapshots?

[telenoar]

Running FreeNAS 11.1-U7 on two separate Storinator chassis.

We're running out of space and were deleting numerous TB's, and I was noticing that the 'Used' and 'Available' volume/storage numbers weren't changing at all. It does appear that the discrepancy is taken up by snapshots.

The thing is... We don't use snapshots. I never created any, and the periodic snapshot and replication tasks are empty. So where would they be "coming from"?! Is there any config/feature in FreeNAS that automatically creates Snapshots in kind of a "recycle bin" capacity, filling them up with deleted files?

And a noob question, to be absolutely sure: If you destroy a snapshot, none of the "normal" data you see in Windows Explorer (or Finder, Bash, etc.) is affected? (No I'm not talking about the secret .zfs folder...) A snapshot represent a past point in time, not the present delta, right? (From what I understand, a snapshot is static, and the present data is the delta. Deleting a snapshot is nothing like normal data deletion, rather it consolidates or settles the delta, and the result is "normal, static" data.)

 

[sretalla]

If you destroy a snapshot, none of the "normal" data you see in Windows Explorer (or Finder, Bash, etc.) is affected?

Correct.

A snapshot represent a past point in time, not the present delta, right?

Actually it's a mix. A snapshot is a copy of the file table at a point in time which is also used to avoid overwriting space that has been freed or changed since the snapshot was taken, so the "contents" of a snapshot are the blocks that were there at the time of the snapshot... some of them may have subsequently been changed in the "current" filesystem, but the snapshot points to the originals as they were (so much of the content can still be there with no change).

So where would they be "coming from"?! Is there any config/feature in FreeNAS that automatically creates Snapshots in kind of a "recycle bin" capacity, filling them up with deleted files?

No, there is no such feature.
Have a look at:
zfs list -t snapshot

And see if the snapshot names (the part after the @ symbol) give anything away.