Solution

Yeah, the drive is dying. As suggested by @[email protected], and @[email protected], I ran a S.M.A.R.T. test (the short option), and received the following report:

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: FAILED!
Drive failure expected in less than 24 hours. SAVE ALL DATA.
Failed Attributes:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x002f   001   001   051    Pre-fail  Always   FAILING_NOW 1473

Original Post

I have a pulled hard drive from an old Western Digital external hard drive. I connected it to my desktop to see what was on it, and, after running fdisk -l (which took a weirdly long time to run while also keeping one core at 100%), it gave the error message:

The primary GPT table is corrupt, but the backup appears OK, so that will be used.

However, trying to mount it resulted in another error saying that the drive doesn’t exist. Looking at dmesg reveals a ton of other errors like the following:

...
[  252.090206] critical target error, dev sde, sector 8 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[  252.090210] Buffer I/O error on dev sde, logical block 1, async page read
[  252.090292] sd 6:0:0:0: [sde] Attached SCSI disk
[  296.776697] sd 6:0:0:0: [sde] tag#13 uas_eh_abort_handler 0 uas-tag 1 inflight: CMD IN 
[  296.776712] sd 6:0:0:0: [sde] tag#13 CDB: ATA command pass through(12)/Blank a1 08 2e 00 01 00 00 00 00 ec 00 00
[  296.796696] scsi host6: uas_eh_device_reset_handler start
[  296.920474] usb 4-6: reset SuperSpeed USB device number 3 using xhci_hcd
[  296.940278] scsi host6: uas_eh_device_reset_handler success
[  300.090562] sd 6:0:0:0: [sde] Unaligned partial completion (resid=12280, sector_sz=512)
[  300.090567] sd 6:0:0:0: [sde] tag#16 CDB: Read(10) 28 00 00 00 00 08 00 00 18 00
[  300.090570] sd 6:0:0:0: [sde] tag#16 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=2s
[  300.090572] sd 6:0:0:0: [sde] tag#16 Sense Key : Hardware Error [current] 
[  300.090573] sd 6:0:0:0: [sde] tag#16 Add. Sense: Internal target failure
[  300.090574] sd 6:0:0:0: [sde] tag#16 CDB: Read(10) 28 00 00 00 00 08 00 00 18 00
[  300.090575] critical target error, dev sde, sector 8 op 0x0:(READ) flags 0x80700 phys_seg 3 prio class 2
[  300.090640] sd 6:0:0:0: [sde] tag#14 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=2s
[  300.090642] sd 6:0:0:0: [sde] tag#14 Sense Key : Hardware Error [current] 
[  300.090643] sd 6:0:0:0: [sde] tag#14 Add. Sense: Internal target failure
[  300.090644] sd 6:0:0:0: [sde] tag#14 CDB: Read(10) 28 00 00 00 00 20 00 00 08 00
[  300.090645] critical target error, dev sde, sector 32 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
[  326.010763] usb 4-6: USB disconnect, device number 3
[  326.010898] sd 6:0:0:0: [sde] tag#18 uas_zap_pending 0 uas-tag 1 inflight: CMD 
[  326.010901] sd 6:0:0:0: [sde] tag#18 CDB: Read(10) 28 00 00 00 00 20 00 00 08 00
[  326.010903] sd 6:0:0:0: [sde] tag#17 uas_zap_pending 0 uas-tag 2 inflight: CMD 
[  326.010905] sd 6:0:0:0: [sde] tag#17 CDB: Read(10) 28 00 00 00 00 08 00 00 08 00
[  326.010919] sd 6:0:0:0: [sde] tag#18 FAILED Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK cmd_age=25s
[  326.010921] sd 6:0:0:0: [sde] tag#18 CDB: Read(10) 28 00 00 00 00 20 00 00 08 00
[  326.010922] I/O error, dev sde, sector 32 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[  326.010925] Buffer I/O error on dev sde, logical block 4, async page read
[  326.010931] sd 6:0:0:0: [sde] tag#17 FAILED Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK cmd_age=25s
[  326.010942] sd 6:0:0:0: [sde] tag#17 CDB: Read(10) 28 00 00 00 00 08 00 00 08 00
[  326.010943] I/O error, dev sde, sector 8 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[  326.010945] Buffer I/O error on dev sde, logical block 1, async page read
[  326.050781] sd 6:0:0:0: [sde] Synchronizing SCSI cache
[  326.270781] sd 6:0:0:0: [sde] Synchronize Cache(10) failed: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
...

Is this drive dead? Is something just corrupt? If there is data on it, would it be straightforward to pull it off?

  • @PriorProject
    3•1 year ago

    That disk certainly isn’t healthy.

    For my own future knowledge, what, exactly, in the logs, led you to that conclusion?

    GPT is the partition scheme that stores the partition table. Very few pieces of software interact with that layer of your storage system. The first GPT table error tells us that, unless we’ve been messing with low-level tools that might break the partition table… the physical disk has probably already lost data. So we’re already primed to suspect a busted disk.

    Then the kernel log snippets you pasted show tons of errors in the block device layer. I know noisy application logs sometimes train us to ignore error messages, but the kernel block device layer does not log out error messages for fun. If you see any log like ERROR sdx where sdx is a block device that stores important data without a backup… you’re about to be in for a rough ride.

    image the whole thing with ddrescue

    Since you mention “image”, I’m assuming that I would need a drive at least equal to the size of the source drive to store the image? The issue is that the source drive is 2TB in size, so I would need to source another 2TB drive (at least) to store the image.

    Yes, though you can pipe ddrescue into gzip or another compressor and if the drive isn’t full and you’re lucky enough to have some decent sized zero’d out regions they’ll compress very well. In the best case, you might only need a disk big enough to hold the live data. In the worst case, yeah, you need a matched disk or bigger.

    Pro tip, buy drives in pairs and automate backups to one of them. If you have a disk you can’t copy to another disk, you almost might as well have no disk. This kind of thing happens, not a lot… but I lose a disk maybe every 3y-5y or so. I have a few disks around… maybe 6 online at any given time. But it’s not like I’m running hundreds of them. They just conk out every now and again and you’ve got to be ready for them.

    • @[email protected]
      2•1 year ago

      Pro tip, buy drives in pairs and automate backups to one of them.

      Honestly I don’t think this is the best way. Best to buy them at different times or buy two from different manufacturers. Chances are that if you buy two identical ones together once one starts to fail the other is not far behind. Or if there is some defect in the batch you could have both fail quickly and within a very short window of each other.

      If you much buy identical drives best to have one be far less active then the other, like be an offline backup rather then a hot backup.

      • @PriorProject
        1•1 year ago

        Yeah fair. This is sound advice.

        I buy matched pairs to mirror, and then offset the purchase of my pair of backup drives. So I end up having 4 copies on two different models. And when my primary disks get full I “promote” my larger backup disks to primary and buy a new/larger pair of backup disks that are big enough to store many snapshots of my primaries. I knew this was too much for OP and tried to simplify… but your approach is equally simple and better.