raid-problems

[   59.174630]  sda: sda1
[   59.175079] sd 0:0:0:0: [sda] Attached SCSI disk
[   59.506931] scsi 1:0:0:0: Direct-Access     HGST HUH 721212ALE604     0    PQ: 0 ANSI: 6
[   59.507449] sd 1:0:0:0: Attached scsi generic sg1 type 0
[   59.507953] sd 1:0:0:0: [sdb] Very big device. Trying to use READ CAPACITY(16).
[   59.508262] sd 1:0:0:0: [sdb] 23437770752 512-byte logical blocks: (12.0 TB/10.9 TiB)
[   59.508277] sd 1:0:0:0: [sdb] 4096-byte physical blocks
[   59.508727] sd 1:0:0:0: [sdb] Write Protect is off
[   59.508743] sd 1:0:0:0: [sdb] Mode Sense: 43 00 00 00
[   59.509179] sd 1:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[   59.559725]  sdb: sdb1
[   59.560395] sd 1:0:0:0: [sdb] Attached SCSI disk
[   59.940392] md/raid:md0: not clean -- starting background reconstruction
[   59.940484] md/raid:md0: device sda1 operational as raid disk 0
[   59.942742] md/raid:md0: cannot start dirty degraded array.
[   59.946471] md/raid:md0: failed to run raid set.
[   59.946574] md: pers->run() failed ...
[78339.103037] /dev/sdb1: Can't open blockdev
[78395.156781] /dev/sdb1: Can't open blockdev