Cache disk showing Unmountable: No file system

[johnnykilo]

I have 2 cache disks and one of them is saying Unmountable: No file system. Looking for help repairing it. Screenshot and diagnostics files attached. Thanks

jordan-diagnostics-20200516-2105.zip

[JorgeB]

6 hours ago, johnnykilo said:

I have 2 cache disks

What happened to the other one?

 

In the meantime try this, on the console type:
 

mkdir /x
mount -o ro,nologreplay /dev/sdb1 /x

If it doesn't mount post the error on the syslog

 

 

[johnnykilo]

Its not in the array in the moment, its in the Unassigned Devices list right now. I was going to try to mount just the good Cache disk when I got a message that the data would be overwritten. My docker.img is on there as well as my appdata. These were both cache only so I need to try to recover the data.

 

Thanks,

 

 

root@Jordan:~# mkdir /x
root@Jordan:~# mount -o ro,nologreplay /dev/sdb1 /x
mount: /x: wrong fs type, bad option, bad superblock on /dev/sdb1, missing codepage or helper program, or other error.

 

[40723.492912] BTRFS info (device sdb1): disabling log replay at mount time
[40723.492914] BTRFS info (device sdb1): disk space caching is enabled
[40723.492916] BTRFS info (device sdb1): has skinny extents
[40723.494229] BTRFS error (device sdb1): parent transid verify failed on 131072 wanted 13771442 found 13769926
[40723.494232] BTRFS error (device sdb1): failed to read chunk root
[40723.500826] BTRFS error (device sdb1): open_ctree failed

[JorgeB]

Looks like that one is toast, btrfs restore is likely the only option, but if the pool was redundant you can try the other device, you can safely assign it after making Unraid forget current pool:

 

Stop the array, unassign current cache device, start array to make Unraid "forget" current cache config, stop array, reassign the other cache device (there can't be an "All existing data on this device will be OVERWRITTEN when array is Started" warning for any cache device), start array.

 

If the other device also doesn't mount see here for other recovery options.

[johnnykilo]

I don't believe the pool is redundant, unless that's the default behavior. I originally had the 120GB SSD as the only cache disk. I decommissioned another server and ended up with the 512GB SSD and figured I'd add it to the cache pool. I'll look in to the btrfs restore. thanks.

[JorgeB]

2 minutes ago, johnnykilo said:

unless that's the default behavior.

It is, though there was a bug for pools created with v6.7.x where it wasn't.

[johnnykilo]

cool, didn't know that. Trying a restore now. Thanks