UnRAID How to rebuild from parity?

Hi guys! Pls hlep!

I have 10 TB parity drive and 8TB+2TB of array drives.

Parity no errors, everything ok.

8 TB drive had some small errors, not a problem.

Don’t ask me why and how, but I ran “badblocks -ws -b 4096 /dev/sde” for 61h (still running) on this 8 TB drive. And then I checked again what this command means and apparently I trashed all data on this drive with it…

What should I do now exactly?

Shall I break this bad blocks test and format this 8 TB in GUI? How is recovering from parity working? Everything in GUI? What are the next steps?


If I understand you correctly, your 8TB data drive has been overwritten so Unraid is likely running in a virtualized drive condition off the parity drive?

First, if the array is in a start-able state, it may be a good idea to make sure you have backups of everything before continuing. PARITY IS NOT BACKUP. It’s always a good idea to have separate backups. Hopefully the array wasn’t active when you corrupted the drive, since the parity drive may have been dutifully doing it’s job and recording the changes you made to your data drive.

Anyway, once you have backups, stop the array and set “no disk” in the impacted drive slot, then start and stop the array. Add the disk back in and restart the array making sure it says the array will be rebuilt next to that option.

With luck everything will be rebuilt from parity and you’ll be good to go.

Please remember to make a separate backup going forward.