This could be bad: Help with parity + data disk errors

[FamilyMan]

No idea how this happened. My last parity check a few weeks ago was fine, no disk errors ever.

I pre-cleared two 10TB disks using the unassigned devices preclear plugin. I restarted the array (clean), then unassigned the 8TB Parity and assigned one of the 10TB to parity and started the array.

Disk 3 started throwing read errors right away. I cancelled the parity build on the new disk and re-added the original parity thinking I might be able to unbalance data off disk3 and have the good parity drive fill in for any read errors. But then original 8TB parity started to rebuild parity, and I figured I should just let it finish. (I think maybe that was a mistake.)

Disk3 eventually quit throwing read errors (after about 7300), and parity finished. But now there's a Red X on parity drive and it has thrown a few errors itself.

 

Anyone have any idea what should I do now ?

tower-diagnostics-20220829-2359.zip

[JorgeB]

Disk3 is failing and since old parity was also overwritten you need to copy everything you can from that disk to other(s), alternatively you can use ddrescue to clone the disk and recover as much as possible.

[FamilyMan]

Thank you. I'll do that.

How could I have handled this better?

[itimpi]

11 minutes ago, FamilyMan said:

How could I have handled this better?

If when you got the original failure once you had described your problem and posted diagnostics so we could confirm there was nothing else obviously wrong we could have given you the steps to get Unraid to accept the original parity disk so that you could then probably get an error-free rebuild of disk3.

 

 In principle it is a good idea to ask for help before letting Unraid do anything you are not sure about.