External USB hard drive undetected by Debian Squeeze
 

The problem:

My external usb hard drive is not detected in Debian Squeeze. Attempting to mount it with KwikDisk results in "special device /dev/sdf1 does not exist." It had worked fine (automounting at boot or login) for some months previous.

Poking around in /dev/, I find no /dev/sdf (it stops at /dev/sde). Running "fdisk -l /dev/sdb" on each of these, excepting /dev/sda (internal hard drive), reveal no partitions.

What changed:

I'm not sure; I didn't keep close tabs on my /dev directory. I use KDE, and plasma crashed on me while playing a flash video. I gave the commands kwin --replace, plasma-desktop, kwin --replace. KDE got choppy after a bit, so I restarted. This stuff with KDE all runs in user-space, so it shouldn't have messed with root-level stuff, right?

Anyway, I suppose that something deleted /dev/sdf, somehow. I suppose it's also possible that the external hard drive fritzed out; I'm going to try booting into Knoppix after it's downloaded and burned to see if Knoppix detects it.

Any ideas, assuming the HD itself isn't the problem?

Hi Avelaval,

using a live-CD is a good Idea. It will help you to verify that the external drive is not damaged. If it's not recognized by the live-CD there's most likely a hardware-problem, maybe the drive itself or the connector. Did you check with another plug/connector/cable?

I don't believe that the drive-issue has something to do with KDE, when it does not show up in /dev it cannot be a KDE-issue. How many drives do you have? you wrote about /dev/sde, isn't that the external drive? as you know, the name in /dev can change, for example from /dev/sdf to /dev/sdg or /dev/sde

Markus

In a terminal issue "tail -f /var/log/messages" before plugging the external drive to your computer. Then plug in the drive and observe the messages in that terminal. If the drive is okay you should see it show up as /dev/sdx and also it's partition(s) as /dev/sdx1 etc.

You can post that output here if you still can't mount your drive - including the command and output when you attempt to mount it.

Looks like it's a hard drive problem: KNOPPIX didn't detect it, changing the USB cord didn't help, and plugging it into different USB ports does nothing.

Tried running "tail -f /var/log/messages" and then plugging the drive in. No new lines of output were produced.

Don't remember ever not having any output. Can you try another hard disk
with the same cable(s), just to eliminate everything but disk?

Couldn't manage to locate another hard drive to try the cables on. However, I found a third cable which also failed (no new output in /var/log/messages). Further, putting an SD card in works fine:

Aug 23 10:11:11 deep-green kernel: [ 2870.766861] sd 8:0:0:0: [sdb] 1987584 512-byte logical blocks: (1.01 GB/970 MiB)
Aug 23 10:11:11 deep-green kernel: [ 2870.769609] sdb: sdb1

EDIT: also tried connecting SD card through an SD-to-USB converter. Worked fine:

Aug 23 11:03:13 deep-green kernel: [ 5993.164015] usb 2-4: new high speed USB device using ehci_hcd and address 4
Aug 23 11:03:14 deep-green kernel: [ 5993.307813] usb 2-4: New USB device found, idVendor=0781, idProduct=b2b5
Aug 23 11:03:14 deep-green kernel: [ 5993.307816] usb 2-4: New USB device strings: Mfr=3, Product=4, SerialNumber=5
Aug 23 11:03:14 deep-green kernel: [ 5993.307819] usb 2-4: Product: MobileMate Reader
Aug 23 11:03:14 deep-green kernel: [ 5993.307821] usb 2-4: Manufacturer: SanDisk
Aug 23 11:03:14 deep-green kernel: [ 5993.307822] usb 2-4: SerialNumber: 071126400030
Aug 23 11:03:14 deep-green kernel: [ 5993.307916] usb 2-4: configuration #1 chosen from 1 choice
Aug 23 11:03:14 deep-green kernel: [ 5993.308590] scsi9 : SCSI emulation for USB Mass Storage devices
Aug 23 11:03:19 deep-green kernel: [ 5998.309241] scsi 9:0:0:0: Direct-Access Generic STORAGE DEVICE 9407 PQ: 0 ANSI: 0
Aug 23 11:03:19 deep-green kernel: [ 5998.309794] sd 9:0:0:0: Attached scsi generic sg7 type 0
Aug 23 11:03:19 deep-green kernel: [ 5998.495608] sd 9:0:0:0: [sdf] 1987584 512-byte logical blocks: (1.01 GB/970 MiB)
Aug 23 11:03:19 deep-green kernel: [ 5998.496723] sd 9:0:0:0: [sdf] Write Protect is off
Aug 23 11:03:19 deep-green kernel: [ 5998.499474] sdf: sdf1
Aug 23 11:03:19 deep-green kernel: [ 5998.502728] sd 9:0:0:0: [sdf] Attached SCSI removable disk

Well, this doesn't look good for the drive. Do you have another computer available to check it with even another machine?

If it's really damaged you'll have to find out if you can restore the data from the drive. Maybe it's only the case damaged, you could install the drive into your computer and hopefully it runs there.

Markus

That's more or less what I was thinking: get a SATA cable to put it into the computer. I'm thinking, maybe a bit optimistically, that the problem is not with the hard drive itself and instead with the USB-to-hard-drive circuit board (because linux and the drive don't seem to be relaying messages).

I'll let you know how it goes... Thanks.

Good luck, hopefully you're data are not lost.

Markus

The hard drive is apparently dead: hooking it up via SATA resulted in a boot up error message along the lines of "sending setreset (drive not ready)" during boot time. Thanks, Markush and Bruce, for your help.

Sounds so ... sorry for your loss.

If you add a SATA-drive to your computer, you'll have to check in the BIOS that the bootsequence is properly set. Other than IDE-drives SATA has no Jumpers, but probably it has to be configured.

Markus