[SOLVED] USB Hard disk with unusual errors

business_kid · 03-03-2021, 11:16 AM

A usb hard disk is going weird on me. I confess to being suspicious of it (slow to mount sometimes). Anyhow, I wanted to pur an OS on it, and it's gone nasty on me. There is data on it, but it's nearly all on another disk.

If I switch it off/on, it invariably fails to work. Unplug and plug in the usb port works better, but now it's showing this:

Code:

root@RoseViolet:~# dmesg |tail
[99689.655665] sd 5:0:0:0: [sdc] 976773168 512-byte logical blocks: (500 GB/466 GiB)
[99689.656167] sd 5:0:0:0: [sdc] Write Protect is off
[99689.656174] sd 5:0:0:0: [sdc] Mode Sense: 00 38 00 00
[99689.656637] sd 5:0:0:0: [sdc] Asking for cache data failed
[99689.656642] sd 5:0:0:0: [sdc] Assuming drive cache: write through
[99689.673901]  sdc: sdc1
[99689.675578] sd 5:0:0:0: [sdc] Attached SCSI disk
[99713.760269] EXT4-fs (sdc1): ext4_check_descriptors: Block bitmap for group 1664 not in group (block 2857740885)!
[99713.760271] EXT4-fs (sdc1): group descriptors corrupted!
[99758.236861] usb 1-4: USB disconnect, device number 16
root@RoseViolet:~# e2fsck -fvy /dev/sdc1
e2fsck 1.46.1 (9-Feb-2021)
e2fsck: No such file or directory while trying to open /dev/sdc1
Possibly non-existent device?

Mount apparently thinks there is a zero length partition. If I try this tomorrow, it may just come alive. I wanted to boot this, but that's obviously silly. Once it's mounted, it's fine. This is a mechanical platter disk some years old. IIRC, this was my first usb drive case. Are there any tricks up anyone's sleeve to sort this?

EDIT: I powered off a while, powered up, let it get up to speed and tried the mount. It actually mounted.

What next?

EDIT2: wrong disk - sorry. The dud says

Code:

root@RoseViolet:~# mount  /dev/sdc1 /mnt/dvd
mount: /mnt/dvd: mount(2) system call failed: Structure needs cleaning.

computersavvy · 03-03-2021, 08:03 PM

I would dismount it, then run fsck on it.
Following that I would use the smartctl tools to test it out.

If it is and has been unreliable there is another possibility not directly related to the physical disk. The USB interface in the drive case may be causing a problem.

business_kid · 03-04-2021, 03:33 AM

I think I have it down. It's a spin-up problem. If it's spinning ok, it seems to read good

EDIT: Let me unsay that

Quote:

root@RoseViolet:~# mount /dev/sdc1 /mnt/dvd
mount: /mnt/dvd: mount(2) system call failed: Structure needs cleaning.
root@RoseViolet:~# e2fsck -fvy /dev/sdc
e2fsck 1.46.1 (9-Feb-2021)
ext2fs_open2: Bad magic number in super-block
e2fsck: Superblock invalid, trying backup blocks...
e2fsck: Bad magic number in super-block while trying to open /dev/sdc

The superblock could not be read or does not describe a valid ext2/ext3/ext4
filesystem. If the device is valid and it really contains an ext2/ext3/ext4
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>
or
e2fsck -b 32768 <device>

/dev/sdc contains `DOS/MBR boot sector; partition 1 : ID=0x83, start-CHS (0x0,32,33), end-CHS (0x3ff,254,63), startsector 2048, 976771072 sectors' data
root@RoseViolet:~# mount /dev/sdc1 /mnt/dvd

The second mount command went out to lunch and stayed out. I tried alternate superblocks, btw. It's cat and mouse.

Note to self: Replace that <expletive deleted>

EDIT2: GOT IT EXACTLY! It's end float! End float is a mechanical term that relates not to play in the bearings, but axial movement along the line around which the shaft rotates. So my disk is in a usb caddy. But I get different errors when the caddy is on it's side, upright, or upside down.