問題：WD外付けハードドライブが取り付けられていません。ドライバにアクセスできません。ノートブックに接続し、約20分後に別の場所とディスクの下のファイルに表示されます。
dmesg出力：
[ 3611.422557] usb 4-2: New USB device found,
[ 3611.422571] usb 4-2: New USB device strings: Mfr=1, Product=2, SerialNumber=5
[ 3611.422575] usb 4-2: Product: Elements 10B8
[ 3611.422578] usb 4-2: Manufacturer: Western Digital
[ 3611.456635] usb-storage 4-2:1.0: USB Mass Storage device detected
[ 3611.456857] scsi host0: usb-storage 4-2:1.0
[ 3611.456952] usbcore: registered new interface driver usb-storage
[ 3611.458659] usbcore: registered new interface driver uas
[ 3612.474692] scsi 0:0:0:0: Direct-Access WD Elements 10B8 1012 PQ: 0 ANSI: 6
[ 3612.475089] sd 0:0:0:0: Attached scsi generic sg0 type 0
[ 3612.476156] sd 0:0:0:0: [sda] Spinning up disk...
[ 3613.497891] .......................
[ 3667.243549] usb 4-2: reset SuperSpeed USB device number 2 using xhci_hcd
[ 3667.264764] ready
[ 3697.960601] usb 4-2: reset SuperSpeed USB device number 2 using xhci_hcd
[ 3878.057148] sd 0:0:0:0: [sda] tag#0 timing out command, waited 180s
[ 4058.131137] sd 0:0:0:0: [sda] tag#0 timing out command, waited 180s
[ 4058.131207] sd 0:0:0:0: [sda] Read Capacity(10) failed: Result: hostbyte=DID_OK driverbyte=DRIVER_OK
[ 4058.131216] sd 0:0:0:0: [sda] Sense Key : Hardware Error [current]
[ 4058.131224] sd 0:0:0:0: [sda] ASC=0x44 <<vendor>>ASCQ=0x81
[ 4058.131231] sd 0:0:0:0: [sda] 0 512-byte logical blocks: (0 B/0 B)
[ 4058.131234] sd 0:0:0:0: [sda] 0-byte physical blocks
[ 4238.177508] sd 0:0:0:0: [sda] tag#0 timing out command, waited 180s
[ 4238.177558] sd 0:0:0:0: [sda] Test WP failed, assume Write Enabled
[ 4418.217232] sd 0:0:0:0: [sda] tag#0 timing out command, waited 180s
[ 4418.217326] sd 0:0:0:0: [sda] Asking for cache data failed
[ 4418.217337] sd 0:0:0:0: [sda] Assuming drive cache: write through
[ 4418.218144] sd 0:0:0:0: [sda] Attached SCSI disk
[ 4448.234842] sd 0:0:0:0: [sda] tag#0 timing out command, waited 30s
[ 5922.916734] sd 0:0:0:0: [sda] tag#0 access beyond end of device
[ 5922.916749] I/O error, dev sda, sector 2 op 0x0:(READ) flags 0x1000 phys_seg 1 prio class 0
[ 5922.916767] EXT4-fs (sda): unable to read superblock