1 Disk has gone unmountable. Data lost

[Psybernoid]

I have 4x2TB drives in my system. 2 of which are parity.

I've lost Disk 1 (sde) with the error Unmountable: Unsupported or no file system.

 

Fair enough, drives fail. However, my main concern is, why hasn't the parity kicked in? These files now appear to be lost.

 

Logs attached. Appreciate any insight.

 

 

totem-diagnostics-20231019-0622.zip

[domrockt]

Hello, did you put an new 2tb in the Array? Then the resilver will „Kick“ in

 

here is what to do https://docs.unraid.net/legacy/FAQ/replacing-a-data-drive/

Edited October 19, 2023 by domrockt

[Psybernoid]

Just done that. Now stating the disk is emulated.

 

However, no data is present. Fortunately I had anything important backed up to another device.

[JorgeB]

Parity won't help with filesystem issues, if the log tree is the only problem this should help:

 

btrfs rescue zero-log /dev/md1p1

 

Then re-start the array.

[Psybernoid]

So...if a drive becomes unmountable with the error I had, Unraid won't recognise it as a failed disk? That's actually terrible.

Edited October 19, 2023 by Psybernoid

[JorgeB]

15 minutes ago, Psybernoid said:

Unraid won't recognise it as a failed disk?

A disabled disk and an unmountable disk are two completely different things, though sometimes a disabled disk can also be unmountable, rebuilding from parity fixes the disable part, repairing the filesystem is a different step, and it also depends to on the filesystem used.

 

P.S. for the typical user, would recommend sticking with XFS, it's usually more robust and easier to recover from fs corruption, though backups of anything important are still necessary.