Parity Errors

[bkastner]

I recently swapped out my 4TB parity drive for a 6TB drive (both were red). I did 2 preclear cycles on the 6TB disk to stress test it before putting it into production, and all seemed well, but I am seeing a few odd things.

 

- I built parity, and then did a parity check. It reported it found 128 errors (I have parity correction turned on). I decided to re-run it as I figured it was maybe having issues with files being written while the check was happening, but the second parity check came back with 128 errors found as well.

- When I look at the GUI it reports 512 errors.

 

MyMain / SMART view doesn't report any problems and neither does the SMART tab in UnMENU, but I am not happy that it keeps thinking it's fixed 128 errors, and the error listing on the main GUI page.

 

Is there anything else I should be checking? Should I be concerned? I can upload a syslog, but for this type of issue I wasn't sure if it's was necessary.

 

[jphipps]

A few of us have had some parity issues and crashes running under the normal unRaid boot.  For some reason if we boot under Xen, the parity check seems to work fine.  Not seeing your logs it is hard to tell if there is another cause, but you may want to give that a try and see what happens.

[bkastner]

Here is my syslog. Hopefully it will shed some light.

 

I am travelling this week, so don't want to remotely reboot into Xen - just in case. I am running in the non-Xen config though, so it's possible it follows your other examples.

 

I never really noticed these issues until I swapped out my parity drive so don't know if there is an issue with the parity build under the later 6.0 betas, or if I just wasn't observant to catch this before.

syslog.zip

[jphipps]

Looks like you have a lot of IO errors occurring on ata7 and ata8 when you get the parity errors.  You may want to shut it down and double check all the cabling and check the smart report on those 2 disks to verify there is no disks errors going on.

[bkastner]

Looks like you have a lot of IO errors occurring on ata7 and ata8 when you get the parity errors.  You may want to shut it down and double check all the cabling and check the smart report on those 2 disks to verify there is no disks errors going on.

 

That's strange. When I look at SMART reports I don't see any errors at all (would IO errors show up there?)

 

Also, I have a Norco 4224 using a backplane, so would guess cabling issues are less likely (I could be wrong here). Unfortunately I am travelling this week, so can't try and reseat drives, but I would guess it's harder to shift a drive in my case to mess up connectivity (again... just a guess).

 

Other than reseating, is there anything else I can try/test remotely?

[jphipps]

The only thing you could probably try is the Xen boot, but anything remote is always risky.  If you modify the syslinux.cfg you can switch the default boot from regular to Xen and reboot.  Most other things would be best being local..

[bkastner]

The only thing you could probably try is the Xen boot, but anything remote is always risky.  If you modify the syslinux.cfg you can switch the default boot from regular to Xen and reboot.  Most other things would be best being local..

 

Thanks. I am rebooting now and will try a parity check under Xen and see what happens.

[bkastner]

So I completed the parity check overnight under Xen and not an issue - no parity corrections and no disk errors reported.

 

Very bizarre. I am going to add a post under defects.