Single parity error, but no drive errors.

[cyrnel]

I just had an unclean shutdown on my new 6.x box when its UPS died. Rebuilt parity and all the drives show clean but the parity message is "Last checked on Mon 01 Feb 2016 12:21:22(today), finding 1 error." Up above each drive is listed with "Errors 0". How does one track this down?

[trurl]

Correcting parity check on unclean shutdown happens because parity might be out-of-sync so sounds like this worked as intended.

[cyrnel]

Of course that makes sense with a soft error. Wish the parity check interface would say something like "corrected x errors on Disk n".

[Frank1940]

Of course that makes sense with a soft error. Wish the parity check interface would say something like "corrected x errors on Disk n".

 

Unfortunately, what was corrected was the bit on the parity disk so that the parity drive now correspondences (with the correct parity) with the data that is on the data drives.  So nothing was corrected on any of the data disks. 

[garycase]

Of course that makes sense with a soft error. Wish the parity check interface would say something like "corrected x errors on Disk n".

 

Mathematically there's no way to know which disk has the incorrect bit, so it's not possible to say that.

 

It's VERY likely that parity errors after an unclean shutdown are indeed on the parity disk ... which is why that's what UnRAID assumes.

 

I presume you did a correcting check -- so the error was indeed corrected.  If not, you should run another parity check to let it fix the error.  [Not a bad idea to just run another check anyway to confirm there are now zero errors]

 

 

[cyrnel]

A guy steps away from the console for a few years and suddenly he forgets all the obvious stuff...

 

Thanks all, I can use it!