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Can't mount my USB 2.0 hard drive

Salutation!

I've been a user of linux for some time now so I'm not a total newbie but I'm not an expert either. However, I'm quite new to forums.

Anyway, I have a problem with a USB 2.0 hard drive 40Gb that I just bought. My computer doesn't want to mount it. I have 4 other USB sticks that are automatically mounted no problem. So I tried the logical thing to do which is mounting the device manually. I tried:

# mount /dev/sda1 /media/usbdisk

after creating the /media/usbdisk directory, but I get this message:

special device /dev/sda1 does not exist

But the fact is that the computer regonises my HD since when I start the Hardware Browser, it identifies it as:

Drive /dev/sda (Geom: 4864/255/63) (Model: FUJITSU MHV2040AH)

When I do the following command: dmesg |grep sda

here's what I get:

SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
sda: unknown partition table
Attached scsi disk sda at scsi0, channel 0, id 0, lun 0
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
sda: unknown partition table
Attached scsi disk sda at scsi1, channel 0, id 0, lun 0
SCSI device sda: 2007040 512-byte hdwr sectors (1028 MB)
sda: Write Protect is off
sda: Mode Sense: 23 00 00 00
sda: assuming drive cache: write through
SCSI device sda: 2007040 512-byte hdwr sectors (1028 MB)
sda: Write Protect is off
sda: Mode Sense: 23 00 00 00
sda: assuming drive cache: write through
sda: sda1
Attached scsi removable disk sda at scsi2, channel 0, id 0, lun 0
SELinux: initialized (dev sda1, type vfat), uses genfs_contexts
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
sda: unknown partition table
Attached scsi disk sda at scsi3, channel 0, id 0, lun 0
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
sda: unknown partition table
Attached scsi disk sda at scsi4, channel 0, id 0, lun 0
VFS: Can't find a valid FAT filesystem on dev sda.
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
SCSI device sda: 78140160 512-byte hdwr sectors (40008 MB)
sda: assuming drive cache: write through
sda: unknown partition table
Attached scsi disk sda at scsi5, channel 0, id 0, lun 0

I've been trying to plug and unplug it a couple of time without success and I've tried one of my sticks to be sure that everything was alright.

I work with fedora core 3 (kernel: 2.6.12-1.1381_FC3). I've been looking around for the solution but everything I've tried so far as failed.

Can anybody help?

partitioning external hard drive

OK.

Looking around, I found out that I need to partition the disk using
fdisk /dev/sda and then format with mkfs.ext3 /dev/sda1

But there's something wrong because when I partition the changes I make don't stay.

Here's what I do:

Quote:

[root@localhost ~]# fdisk /dev/sda
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.

The number of cylinders for this disk is set to 38154.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
(e.g., DOS FDISK, OS/2 FDISK)
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

Command (m for help): p

Disk /dev/sda: 40.0 GB, 40007761920 bytes
64 heads, 32 sectors/track, 38154 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Device Boot Start End Blocks Id System

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-38154, default 1): 1
Last cylinder or +size or +sizeM or +sizeK (1-38154, default 38154): 38154

Command (m for help): t
Selected partition 1
Hex code (type L to list codes): 83

Command (m for help): p

Disk /dev/sda: 40.0 GB, 40007761920 bytes
64 heads, 32 sectors/track, 38154 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Device Boot Start End Blocks Id System
/dev/sda1 1 38154 39069680 83 Linux

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

So it is obviously creating a /dev/sda1 partition at this stage. However, when I try to format I get this:

Quote:

[root@localhost ~]# mkfs.ext3 /dev/sda1
mke2fs 1.38 (30-Jun-2005)
Could not stat /dev/sda1 --- No such file or directory

The device apparently does not exist; did you specify it correctly?

And when I do fdisk /dev/sda again, the /dev/sda1 partition is not there.

Any idea anyone?

OK, forget everything I said. Tried it on another computer that runs with Unbutu and got the same result. Then I discovered that even windoze xp can't make the thing work. Probably bought a defective unit.

Welcome to LQ lltbreg and thanks for posting back with the update. Initially it sounded like the drive just needed to be formatted, but if you tried it with 3 different systems and none of them recognized it, I'd agree that it could be defective. Good luck with it

Thank you!

And yes. The problem was a defective unit. I had it changed and my new drive works like a charm. It even automouts so no problem anymore.:D