Parity Sync Errors

[ecnal.magnus]

I am continually getting errors during a parity check. One just finished with 150 errors, and the one I ran a week ago had 595 errors. I send all logging to a syslog server, but I don't really know which log to look in or what to look for. I don't see anything wrong when I look at the S.M.A.R.T. information of each disk. I have a 15 drive array with dual parity. I am happy to provide any further information you guys might need. I have been running Unraid for about two years now. I am relatively technologically proficient. I can certainly follow directions well. Any insight would be appreciated.

[JorgeB]

Run two consecutive parity checks without rebooting and post the diagnostics, or if you didn't yet reboot since that first check you ran just post current diags.

[ecnal.magnus]

I have rebooted since the one with 595 errors. I will start another check now. The last one's duration was "2 days, 20 hours, 37 minutes, 52 seconds. Average speed: 64.8 MB/s" so it will be a few days before I can report back.

[ecnal.magnus]

The latest parity check completed with no errors. It has not done that in a month. I don't know what the difference is except MAYBE the others had all been after a reboot? I attached the diagnostics. Consequently, after any reboot, I have always had 5 parity errors the next check that ran. I found some forum posts discussing a certain SAS controller or something that might cause such a thing. I have moved my parity disks off of my SAS controller, to just a PCIe x4 SATA expansion card, and those 5 errors always show up after a boot. Just thought it couldn't hurt to include that information. Anyway, hopefully this is nothing, but if the diagnostics show something wrong, I would be interested in knowing exactly what it is you look for in such things? Thanks in advance.

ecnal-diagnostics-20230709-2007.zip

[JorgeB]

If it's only after a reboot, and always 5 sync errors, it might be a controller.

[ecnal.magnus]

Three checks in a row were multiple hundreds of errors. But then the there were none, and now I rebooted and ran another one and it had 5 errors again. I don't know what to do about the 5 errors. Do you think that over time getting those 5 errors constantly will cause me problems?

[JorgeB]

Difficult to say for sure, but it's not good.

[ecnal.magnus]

So, a few months back I moved the parity drives from the SAS controller to a standard PCIe SATA controller, thinking that would solve the sync errors issue, but those same 5 errors have continued. I think I will move both parity drives to motherboard connectors and see if that eliminates the errors. Thank you for your input. I am going to mark this as solved.