To preface this I am fairly new to Unraid, so apologies if my explanation is not super clear. A few months ago, I logged into the web GUI to see thousands of messages saying "BTRFS missing devices /dev/nvme0n1". I ran 'btrfs dev stats' on /dev/nvme0n1p1 to get the following:

 

 

I replaced both nvme1n1 and nvme0n1 (both pool devices -- both were Samsung Pro 980 drives which are known to have problems, I replaced the other just to be sure). I booted up the Unraid server, precleared the disks and assigned them back. Upon starting the array they appear as "Unmountable: No pool uuid".

 

I was hoping I would just have the option to rebuild them from parity, but it doesn't appear as an option.

 

Any help would be much appreciated! Thank you.

 

 

 

Edited February 2, 20233 yr by 0palescent

Pool devices are not in the parity array so you can't rebuild from parity..

 

I assume they are unmountable because you haven't formatted them yet, but of course they will be empty then.

 

Do you still have the original disks? Were they mountable before you removed them?

 

Here is the wiki related to replacing pool disks.

 

https://wiki.unraid.net/Manual/Storage_Management#Replace_a_disk_in_a_pool

 

Probably what we will need to see is the diagnostics with the original disks assigned and the array started.

 

Don't do anything without further advice.