硬碟spin retry - Linux

抱歉不知道怎麼下標題

剛剛電腦用到一半,突然聽到硬碟不斷spin up -> down -> up ->down.....
打開原本己經開的terminal
$sudo smartctl -a | less
/usr/bin/sudo: xxx IO error
/usr/bin/less: xxx IO error

可是echo /*正常
用sysrq關機,10min後重開進single user mode
smartctl -a /dev/sda
spin retry count = 0 .......?

去看/var/log/messages
Jan 11 19:10:04 dorm kernel: [ 2210.629097] ata6: lost interrupt (Status 0x50)
Jan 11 19:10:04 dorm kernel: [ 2210.629119] ata6.01: exception Emask 0x0 SAct 0x
0 SErr 0x0 action 0x6 frozen
Jan 11 19:10:04 dorm kernel: [ 2210.629123] ata6.01: failed command: WRITE DMA
Jan 11 19:10:04 dorm kernel: [ 2210.629127] ata6.01: cmd ca/00:08:c0:c4:60/00:00
:00:00:00/f0 tag 0 dma 4096 out
Jan 11 19:10:04 dorm kernel: [ 2210.629127] res 40/00:00:00:4f:c2/00:00
:00:00:00/10 Emask 0x4 (timeout)
Jan 11 19:10:04 dorm kernel: [ 2210.629130] ata6.01: status: { DRDY }
Jan 11 19:10:04 dorm kernel: [ 2210.629150] ata6: soft resetting link
Jan 11 19:10:05 dorm kernel: [ 2210.833710] ata6.01: configured for UDMA/100
Jan 11 19:10:05 dorm kernel: [ 2210.833718] ata6.01: device reported invalid CHS
sector 0
Jan 11 19:10:05 dorm kernel: [ 2210.833730] ata6: EH complete

可是如果硬碟自己掛了go offline,為什麼這段log存得進去？

還是說我的OS瘋了,硬碟本身是無辜的？

sda=WD 500G blue (aaks) if this matters

順便問一下最近的新硬碟有沒有什麼特別要注意的點？
好久沒看這一塊了

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