After an unclean shutdown my cache drive (SanDisk Ultra SSD) is unmountable. I ran the filesystem check which found some errors (below), but I've no idea what they mean so though it best to check before powering through with the repair flag. I've also found mixed advice on whether to start the array in maintenance mode for BTRFS filesystem repair, the gui checker will only run with it in maintenance mode though so it'd need to be command line. I've also seen recommendations to scrub the drive, but that option isn't working through the gui (says array must be started, even when it is, perhaps because the cache pool isn't mounted).

 

I've tried a full shutdown and reboot to no avail. I'd love to get the data back if I can, I'm not as on top of backups as I should be, but it's not the end of the world if I can't. 

 

[1/7] checking root items
[2/7] checking extents
ref mismatch on [322373746688 16384] extent item 1099503796588, found 0
owner ref check failed [322373746688 16384]
tree extent[322373763072, 16384] root 717075095356440578 has no tree block found
tree extent[322373763072, 16384] root 2 has no backref item in extent tree
incorrect global backref count on 322373763072 found 2 wanted 1
backpointer mismatch on [322373763072 16384]
ERROR: errors found in extent allocation tree or chunk allocation
[3/7] checking free space tree
[4/7] checking fs roots
[5/7] checking only csums items (without verifying data)
[6/7] checking root refs
[7/7] checking quota groups skipped (not enabled on this FS)
Opening filesystem to check...
Checking filesystem on /dev/sdb1
UUID: f94fcb27-4873-45ee-a90b-41e595fee682
found 225096318976 bytes used, error(s) found
total csum bytes: 208369676
total tree bytes: 1308786688
total fs tree bytes: 499630080
total extent tree bytes: 453361664
btree space waste bytes: 347769243
file data blocks allocated: 853185277952
 referenced 195645399040

coppermind-diagnostics-20250225-2118.zip

Type:

 

btrfs rescue zero-log /dev/sdb1

 

Then restart the array and post new diags