It appears that last Friday night Unraid decided to deleted all the files that were at the root of all of my shares.  In two cases were the share had no subfolders, the entire share was deleted with the files.  Any file that was in a subfolder of any share was not deleted. As my Unraid server is primally used as a Plex server, the lost was ~10TB of movie files, as these were at the root of the share.  

 

Unfortunately, before I released the extent of the issue I had, I rebooted the server and lost the log. So I'm actually guessing the files were "deleted".  The files are gone, however it was done.  I didn't think about how rebooting an OS that runs completely in ram would be an issue for things like log retention. Probably should have thought that thought a bit more, but I'm new to the ways of Unraid.

 

The server had been running for at least three weeks without issue before this happened.  My drives are all BTRFS formatted with two parity and two cache drives.  I could not find any scheduled jobs for Friday that might have kicked this off.  I can't find a system setting that explains what happened.  I'm at a complete lost as to what could have caused this, so I really hope someone here can help me as to the cause of this.

 

As for recovering my files I assume I'm going to have to use a file recovery utility like 'btrfs restore'. So, I'm mostly looking for root cause here unless there is an "easy" way to recover that I don't know about.  I just want to make sure this doesn't happen again.

 

Here is my log with my array online. For what it's worth.

unraidserver-syslog-20211019-0657.zip

I too have found files variously deleted. Numerous times.. I have no cause as to why.