Aww, shucks.
After 7 years, one of the two 6TB Western Digital Red drives that forms half of my RAID1 mirror failed to come up after a server reboot: [ 19.762832] ata2.00: exception Emask 0x0 SAct 0x100 SErr 0x0 action 0x0 [ 19.762838] ata2.00: irq_stat 0x40000008 [ 19.762841] ata2.00: failed command: READ FPDMA QUEUED [ 19.762847] ata2.00: cmd 60/08:40:08:00:00/00:00:00:00:00/40 tag 8 ncq dma 4096 in res 41/40:00:09:00:00/00:00:00:00:00/00 Emask 0x409 (media error) <F> [ 19.762850] ata2.00: status: { DRDY ERR } [ 19.762852] ata2.00: error: { UNC } [ 19.764196] ata2.00: configured for UDMA/133 [ 19.764212] sd 3:0:0:0: [sdd] tag#8 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 19.764215] sd 3:0:0:0: [sdd] tag#8 Sense Key : Medium Error [curre...