Hey all, been a rough week so bear with me while I explain the full situation.

My setup:

• Unraid 7.2- single parity

• Parity: 16TB Seagate Exos (sdd)

• Disk 1: new 16TB Exos (sdi) - not yet rebuilt

• Disk 2: MISSING - 10TB Seagate Exos ST10000NM0086 - physically dead, not detected at all

• Disks 3-8: all healthy, all green

What happened:

About 2 weeks ago Disk 1 (was a 10TB Exos) started throwing critical medium errors and internal target failures. Bought a 12TB IronWolf Pro as replacement, rebuilt successfully, parity was valid, all good.

Few days later the IronWolf Pro died. Traced it back to a dodgy custom PSU cable that I believe has now killed three drives total - the original 10TB Exos, the 12TB IronWolf Pro replacement, and now a second 10TB Exos that was Disk 2. All three were on the same custom cable. Cable has been pulled and replaced with stock PSU cables.

Bought a 16TB Exos as replacement for Disk 1. Installed it tonight. While installing it, Disk 2 (the second 10TB Exos) also failed and is now completely dead and undetectable. So now I have two missing drives simultaneously and Unraid is giving me "Too many wrong and/or missing disks - invalid configuration."

The timeline:

• Disk 1 rebuild onto the IronWolf Pro completed fully - confirmed healthy for several days

• Parity was valid after that rebuild completed

• Disk 2 died AFTER that rebuild completed

• Parity has not been touched or modified since the Disk 1 rebuild finished

• New 16TB Exos is sitting in Disk 1's slot - unassigned and unformatted

What I want to avoid:

I know New Config + parity sync is the nuclear option here and will treat the new Disk 1 as blank, losing whatever was on it. The data on Disk 2 is already gone - I accept that.

What I'm hoping is that since parity was valid and clean after the Disk 1 rebuild just days ago, and Disk 2 died after that, there might be a way to:

1. Tell Unraid that Disk 2 is permanently gone

2. Use the existing valid parity to rebuild Disk 1 onto the new 16TB

Is this possible with a specific procedure, or is New Config + parity sync my only option?

What I haven't done:

• Have NOT run New Config

• Have NOT started the array

• Have NOT formatted anything

• Server is currently stopped

Thanks in advance - happy to provide diagnostics, syslog, anything needed.

Edited March 26Mar 26 by ModulatedDreams

You cannot rebuild any drives with single parity and two bad disks. You can do a new config to recover the remaining disks.

12 hours ago, JorgeB said:

You cannot rebuild any drives with single parity and two bad disks. You can do a new config to recover the remaining disks.

This was my thought but had to see if anyone had any magic input haha.

Thank you!