Odd thing happening.  So a couple days ago I noticed one of my drives  (drive 3 I believe) got unmounted. Did a smart check on the HDD's and it had no issue. Created a new config with the old settings, and it started up. Did the parity check and no problems. My drives are 8TB's so the parity check can easily take up to about 12 hours. I had no issues during that time.  Now the next day I wake up and same thing happens.  This time its the parity #1 and parity #2,  reseated my HBA and associated cables.  (My setup is onboard sata for cache and unassigned drives, HBA to a DAS for the array)  So again it runs thru 12 hours or parity no problems. And of course the drive gets unmounted again after a couple of hours of idle. It seems that my issues are being localized to the array. So my guess is either a HDD going bad, a HBA going bad, or the power supply in either machine going bad.  Does anyone else have any guesses? Logs are provided.
Thanks for your time!

tower-diagnostics-20180922-0318.zip

You say unmounted but I'm pretty sure you mean disabled. Very different concepts. Was there a red X?

And New Config wasn't really the right way to try to fix this, though it probably didn't hurt anything.

 

I'm on mobile right now so haven't looked at diagnostics. Don't do anything else without further advice.

I won't be available for several more hours at least so hopefully someone else will step up.

Yes it has a red X, and thanks

Looks like a problem with the HBA, make sure it's well seated and/or try a different slot if available.