I've reset system to factory default yesterday and it was sinking over night. To my surprise I found it hanged in the morning and after reboot it is unable to find any volumes:
Aug 26 22:11:24 ReadyNAS1 kernel: ata4: hard resetting link Aug 26 22:11:24 ReadyNAS1 kernel: ata4: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Aug 26 22:11:24 ReadyNAS1 kernel: ata4.00: configured for UDMA/133 Aug 26 22:11:24 ReadyNAS1 kernel: ata4.00: device reported invalid CHS sector 0 Aug 26 22:11:24 ReadyNAS1 last message repeated 10 times Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] Unhandled error code Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] CDB: Read(16): 88 00 00 00 00 01 50 38 79 48 00 00 04 00 00 00 Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408392 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408400 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408408 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408416 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408424 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408432 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408440 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408448 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408456 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: md/raid:md2: read error not correctable (sector 5631408464 on sdd3). Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] Unhandled error code Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] CDB: Read(16): 88 00 00 00 00 01 50 38 7d 48 00 00 04 00 00 00 Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] Unhandled error code Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT Aug 26 22:11:24 ReadyNAS1 kernel: sd 3:0:0:0: [sdd] CDB: Read(16): 88 00 00 00 00 01 50 38 81 48 00 00 04 00 00 00 Aug 26 22:11:24 ReadyNAS1 kernel: ata4: EH complete Aug 26 22:11:24 ReadyNAS1 kernel: md: md2: recovery done. Aug 26 22:11:52 ReadyNAS1 kernel: quiet_error: 374 callbacks suppressed Aug 26 22:11:52 ReadyNAS1 kernel: lost page write due to I/O error on dm-0 Aug 26 22:11:52 ReadyNAS1 RAIDiator: RAID sync finished on volume C. The array is still in degraded mode, however. Thi s can be caused by a disk sync failure or failed disks in a multi-parity disk array.
On reboot:
ug 27 10:42:24 ReadyNAS1 kernel: bio: create slab <bio-1> at 1 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid1:md0: not clean -- starting background reconstruction Aug 27 10:42:24 ReadyNAS1 kernel: md/raid1:md0: active with 6 out of 6 mirrors Aug 27 10:42:24 ReadyNAS1 kernel: md0: detected capacity change from 0 to 4293906432 Aug 27 10:42:24 ReadyNAS1 kernel: md: resync of RAID array md0 Aug 27 10:42:24 ReadyNAS1 kernel: md: minimum _guaranteed_ speed: 1000 KB/sec/disk. Aug 27 10:42:24 ReadyNAS1 kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for re sync. Aug 27 10:42:24 ReadyNAS1 kernel: md: using 128k window, over a total of 4193268 blocks. Aug 27 10:42:24 ReadyNAS1 kernel: md0: unknown partition table Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdb2> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdc2> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdd2> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sde2> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdf2> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sda2> Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: device sda2 operational as raid disk 0 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: device sdf2 operational as raid disk 5 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: device sde2 operational as raid disk 4 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: device sdd2 operational as raid disk 3 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: device sdc2 operational as raid disk 2 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: device sdb2 operational as raid disk 1 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: allocated 6372kB Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md1: raid level 6 active with 6 out of 6 devices, algorithm 2 Aug 27 10:42:24 ReadyNAS1 kernel: md1: detected capacity change from 0 to 2147221504 Aug 27 10:42:24 ReadyNAS1 kernel: md1: unknown partition table Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdb3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdc3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdd3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sde3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdf3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sda3> Aug 27 10:42:24 ReadyNAS1 kernel: md: kicking non-fresh sdd3 from array! Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdd3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdd3) Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sda3 operational as raid disk 0 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sde3 operational as raid disk 4 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sdc3 operational as raid disk 2 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sdb3 operational as raid disk 1 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: allocated 6372kB Aug 27 10:42:24 ReadyNAS1 kernel: md: md2 stopped. Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sda3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sda3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdf3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdf3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sde3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sde3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdc3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdc3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdb3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdb3) Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdb3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdc3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdd3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sde3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sdf3> Aug 27 10:42:24 ReadyNAS1 kernel: md: bind<sda3> Aug 27 10:42:24 ReadyNAS1 kernel: md: kicking non-fresh sdd3 from array! Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdd3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdd3) Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sda3 operational as raid disk 0 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sde3 operational as raid disk 4 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sdc3 operational as raid disk 2 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: device sdb3 operational as raid disk 1 Aug 27 10:42:24 ReadyNAS1 kernel: md/raid:md2: allocated 6372kB Aug 27 10:42:24 ReadyNAS1 kernel: md: md2 stopped. Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sda3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sda3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdf3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdf3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sde3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sde3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdc3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdc3) Aug 27 10:42:24 ReadyNAS1 kernel: md: unbind<sdb3> Aug 27 10:42:24 ReadyNAS1 kernel: md: export_rdev(sdb3)
so as you see md2 volume is gone for some reason and as such Volume is not being detected
