Occasionally i'll check my server and the cache drive seems to have dropped.  It's listed under 'unassigned devices'.  It's the same disk every time.  Both cache drives are about a year old (Samsung 850 Pros).  I attached a photo for reference.

 

 

Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:00 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:03 Servo kernel: btrfs_dev_stat_print_on_error: 1092 callbacks suppressed
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061954, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061955, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061956, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061957, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061958, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061959, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061960, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061961, rd 31910608, flush 2268688, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061961, rd 31910608, flush 2268689, corrupt 0, gen 0
Feb 17 15:20:03 Servo kernel: BTRFS error (device sdg1): bdev /dev/sdl1 errs: wr 74061962, rd 31910608, flush 2268689, corrupt 0, gen 0
Feb 17 15:20:05 Servo kernel: btrfs_end_buffer_write_sync: 63 callbacks suppressed
Feb 17 15:20:05 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:05 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:05 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1
Feb 17 15:20:05 Servo kernel: BTRFS warning (device sdg1): lost page write due to IO error on /dev/sdl1

 

Any idea if this is a drive issue/unraid issue?

Most commonly a cable issue, replace both the SATA and power cable to rule them out.

 

Also update to v6.3.2, you should get a system notification if it happens again.

 

You'll need to run a scrub and check that all errors are correctable when that SSD is re-assigned.

 

 

Swapped both cables and looks good so far. Ran a scrub and corrected a bunch of errors. Thanks!

Keep an eye on it, if it happens again grab the diagnostics before rebooting and post them.