Okay quick rundown, previous parity disk was 18tb, I bought a 20 TB disk, I swapped out my parity disk, it recalculated parity just fine.

 

I then went to replace an 8tb array disk with the former 18 tb parity disk and ran into problems, I started messing with drives, locating them etc. Cause I hadnt done that and it was a pain in the ass finding stuff. replaced 8tb array disk with 18tb disk and all hell broke loose.  I kept getting read errors on  random disks during the disk rebuild.  I noticed that it happened to one or more of the 4 drives connected to my SAS HBA, so I replaced that cable.

It appears that solved the issue, however now I am attempting to rebuild the disk again, and get errors on the newly added disk instead of read errors on the others. I am currently running a read check and it has already returned errors on the parity disk, so I am assuming during the failed rebuilds with the bad cable I got some corruption, errors whatever it may be.

So now I have no DISK 5 because that was the disk I replaced, I cannot roll back to the old disk as it already thinks it needs to be 18 tb not 8 tb. And I cannot rebuild because of parity errors.

Where do I proceed from here?

I do have some spare 8tb disks, can I add a disk to the array in its current state or will that fail too?

I could also copy the data to an unassigned disk, then just remove disk 5 from the array I guess run a parity check with fix errors, then copy the data back?

It's just media, but its 7.66 TB of media I would HIGHLY prefer not to download again. It's really not the end of the world but not ideal either, plus this gives me the opportunity to figure it out while its not important data.

I did attach diagnostics for shits and giggles, but I feel like its mostly obvious? but what do I know.

Thanks!

 

 

Edited April 24, 20251 yr by beleaguered-carriage6758
Clarity

Reboot and post new diags after array start.

new Diagnostic file after reboot uploaded.

unraid-diagnostics-20250424-0844.zip

No errors so far and parity looks healthy, try replacing both cables and rebuilding again.

 

 

I only had the 1 spare cable on hand, I ordered another I will replace it when it gets here tomorrow and give it a shot.

I guess if anyone wants to know or looks up this thread, I replaced both cables, but there were partiy errors for sure. So I put the old disk back in after replacing new cables, and then went into tools>>New config, I built a new config but I saved all the disk locations, so it essentially just deleted parity, and it rebuilt fine from the old disk.

I am now back to where  I was before, replaced the smaller drive with the bigger drive and rebuilding that disk, I am about 3 hours in, no errors.