[33743.751807] BTRFS: device label 1 devid 10 transid 56073 /dev/sds
[33743.752575] BTRFS info (device sds): disk space caching is enabled
[33743.752582] BTRFS: has skinny extents
[33743.753289] BTRFS: failed to read the system array on sds
[33743.766480] BTRFS: open_ctree failed
[137608.302297] BTRFS: device label 1 devid 2 transid 56073 /dev/sdk
[137608.303125] BTRFS info (device sdk): disk space caching is enabled
[137608.303130] BTRFS: has skinny extents
[137608.303815] BTRFS: failed to read the system array on sdk
[137608.317389] BTRFS: open_ctree failed
[137719.623692] BTRFS warning (device sdk): 'recovery' is deprecated, use 'usebackuproot' instead
[137719.623699] BTRFS info (device sdk): trying to use backup root at mount time
[137719.623703] BTRFS info (device sdk): disk space caching is enabled
[137719.623705] BTRFS: has skinny extents
[137719.625938] BTRFS: failed to read the system array on sdk
[137719.643320] BTRFS: open_ctree failed
[149643.672150] BTRFS: device label 1 devid 5 transid 56073 /dev/sdn
[149643.673609] BTRFS info (device sdn): disk space caching is enabled
[149643.673614] BTRFS: has skinny extents
[149643.674758] BTRFS: failed to read the system array on sdn
[149643.687444] BTRFS: open_ctree failed
[root@rockstor ~]#