I have 4 8TB Western Digital Red drives arranged in a RAID6 for 24TB of
storage. I suddenly found two of the drives in the array experiencing
errors such as this (from dmesg):
[62414.859601] sd 2:0:0:0: [sdc] tag#0 FAILED Result: hostbyte=DID_OK
driverbyte=DRIVER_SENSE
[62414.859609] sd 2:0:0:0: [sdc] tag#0 Sense Key : Illegal Request
[current]
[62414.859614] sd 2:0:0:0: [sdc] tag#0 Add. Sense: Invalid field in cdb
[62414.859621] sd 2:0:0:0: [sdc] tag#0 CDB: Read(16) 88 00 00 00 00 00
00 00 00 08 00 00 00 08 00 00
[62414.859625] print_req_error: critical target error, dev sdc, sector 8
[62414.859633] Buffer I/O error on dev sdc, logical block 1, async
page read
and this:
[63594.812160] sd 3:0:0:1: [sde] tag#0 FAILED Result: hostbyte=DID_OK
driverbyte=DRIVER_SENSE
[63594.812167] sd 3:0:0:1: [sde] tag#0 Sense Key : Medium Error [current]
[63594.812171] sd 3:0:0:1: [sde] tag#0 Add. Sense: Unrecovered read error
[63594.812176] sd 3:0:0:1: [sde] tag#0 CDB: Read(16) 88 00 00 00 00 00
00 00 00 00 00 00 02 00 00 00
[63594.812180] print_req_error: critical medium error, dev sde, sector 0
[63594.945407] sd 3:0:0:1: [sde] tag#0 FAILED Result: hostbyte=DID_OK
driverbyte=DRIVER_SENSE
[63594.945413] sd 3:0:0:1: [sde] tag#0 Sense Key : Medium Error [current]
[63594.945417] sd 3:0:0:1: [sde] tag#0 Add. Sense: Unrecovered read error
[63594.945423] sd 3:0:0:1: [sde] tag#0 CDB: Read(16) 88 00 00 00 00 00
00 00 00 08 00 00 00 08 00 00
[63594.945426] print_req_error: critical medium error, dev sde, sector 8
Now when I view these drives they appear empty without any partitions or
filesystem information.
Attempting to read the raw contents of the drives, e.g., with pv, leads
to the command failing immediately.
