Hello.  I have an unRAID 6.4.1 server with dual parity that has a current uptime of 164 days (so no recent unplanned/sudden shutdowns).  Today's monthly parity check returned 272 errors.  However, there were 0 reported write Errors across my collection of disks.  During the check I received warnings about a couple offline uncorrectable/pending sector counts on a disk.  I've attached full diagnostics, but am hoping someone might be able to answer a few questions?

 

I have a hot spare I can swap in.  Presumably I should do so now on that disk reporting warnings?

 

Has any data been lost?  I know when there are write errors the disk turns red and you can rebuild it from parity, but in my case unRAID still reports disk status as good (green).

 

If you have monthly parity checks set up, are those "correcting" checks, or "non-correcting"?  If the former, did I just overwrite (presumably) good parity with bad data from the failing disk?

 

Thanks for any help you could provide!

hyperion-diagnostics-20180801-1850.zip

Edited August 2, 20187 yr by Gizmotoy

I ran a follow-up parity check to see if it would complete successfully, and it did not.  The disk failed during the check, so I guess my hand was forced.  I cancelled the check and I'm currently rebuilding the disk from my hot spare.  New log attached.

 

Hopefully there was no data loss?

hyperion-diagnostics-20180802-1718.zip

On 8/3/2018 at 1:20 AM, Gizmotoy said:

Hopefully there was no data loss?

There could be some data corruption since you did a correct check and parity was wrongly updated when the disk started to fail, regular parity checks should always be non correct.

 

Also your SSD needs a new SATA cable.

Bummer.  I'm super-paranoid about preserving parity and having spare disks on-hand, and all for nothing because I screwed up a setting somewhere.  Too bad there wasn't some kind of warning to protect me from myself.  There's no mention of the possibility of data loss in the help for that option.

 

I've corrected the setting and the disk is rebuilt.  Now I need to start searching for corrupted files somehow.  Looks like if I can get ffmpeg installed there's an option for searching the videos, so I'll start there.

 

Edit: Going back through the forums, I remember now that there's a lot of dispute over the correct parity check settings.  I guess that's how I ended up here.  Presumably what I have is not the default.

 

I've got a non-correcting check running just to see where the array stands.  Presumably parity errors indicates there was definitively data loss, and no parity errors indicates there may be data loss.  Everything on my array is replaceable, but it would be nice to figure out which files are affected.

Edited August 6, 20187 yr by Gizmotoy