Cache drive errors then read-only

[gep]

The docker image errors out and goes read only, then /mnt/user/media goes read only.

Tried deleting and recreating docker.img and it worked for a few minutes then same errors came back.

SMART check in cache drive shows no errors.

Have a new cache drive can replace or ideally add to pool if this cache drive is ok.

 

Errors:

BTRFS error (device sdd1): bad tree block start, want 175554560 have 9470129656584428157

BTRFS warning (device sdd1): sdd1 checksum verify failed on 315736064 wanted BD9417A4 found 3FA6F8FF level 0

 

BTRFS error (device sdd1): pending csums is 4096

loop: Write error at byte offset 2158243840, length 4096.

print_req_error: I/O error, dev loop2, sector 4215320

kernel: BTRFS error (device loop2): bdev /dev/loop2 errs: wr 1, rd 0, flush 0, corrupt 0, gen 0

loop: Write error at byte offset 2158243840, length 4096.

print_req_error: I/O error, dev loop2, sector 4215320

BTRFS error (device loop2): bdev /dev/loop2 errs: wr 2, rd 0, flush 0, corrupt 0, gen 0

ntpd[1704]: kernel reports TIME_ERROR: 0x41: Clock Unsynchronized

 

Tried to copy all of cache of to array but the errors occur and all goes read only.

See no errors about the array and data looks good there.

 

tower-diagnostics-20200601-2145.zip

[JorgeB]

There's filesystem corruption on cache, best bet it to backup, re-format and restore any data there.

[gep]

What is the best way to backup the data?

The array is going read-only when the cache drive errors. I tried going into safe mode and mounting array as mentioned in

Except I can't mount sdc1, or sde1 drives for my array.  Errors with: "is not a block device"

Array is xfs

 

I could try scp though may lose permissions. 

 

[JorgeB]

There are some recovery options here:

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?do=findComment&comment=543490