usb drive detected by not accessible?

Kirath · 09-26-2007, 11:01 AM

I'm having a problem accessing an external USB disk on a Red Hat ES 4 system.

lsusb sees the device:

Code:

Bus 010 Device 001: ID 0000:0000
Bus 009 Device 001: ID 0000:0000
Bus 008 Device 001: ID 0000:0000
Bus 007 Device 001: ID 0000:0000
Bus 006 Device 001: ID 0000:0000
Bus 005 Device 001: ID 0000:0000
Bus 004 Device 004: ID 0bc2:3000 Seagate RSS LLC
Bus 004 Device 001: ID 0000:0000
Bus 003 Device 001: ID 0000:0000
Bus 002 Device 001: ID 0000:0000
Bus 001 Device 001: ID 0000:0000

But in /var/log/messages I get:

Code:

Sep 26 11:59:27 localhost kernel: usb 4-5: new high speed USB device using addr4
Sep 26 11:59:27 localhost kernel: scsi3 : SCSI emulation for USB Mass Storage ds
Sep 26 11:59:27 localhost kernel:   Vendor: Seagate   Model: FreeAgentDesktop  D
Sep 26 11:59:27 localhost kernel:   Type:   Direct-Access                      2
Sep 26 11:59:30 localhost kernel: sda: Spinning up disk....ready                
Sep 26 11:59:30 localhost kernel: SCSI device sda: 976773168 512-byte hdwr sect)
Sep 26 11:59:30 localhost kernel: sda: assuming drive cache: write through 
Sep 26 11:59:30 localhost kernel: SCSI device sda: 976773168 512-byte hdwr sect)
Sep 26 11:59:30 localhost kernel: sda: assuming drive cache: write through 
Sep 26 11:59:31 localhost kernel:  sda: sda1
Sep 26 11:59:31 localhost kernel: Attached scsi disk sda at scsi3, channel 0, i0
Sep 26 11:59:31 localhost scsi.agent[3973]: disk at /devices/pci0000:00/0000:000
Sep 26 11:59:48 localhost hald[2476]: Timed out waiting for hotplug event 683. 3

Upon searching I've seen complaints like this but no fixes.. I'm sure there's something I am missing could someone point me in the right direction? Even a link so a solution I've missed in searching would be appreciately greatly. This is frustrating because it has worked on this system before. Thanks...

jiml8 · 09-26-2007, 11:07 AM

So what is the problem? Drive is detected and added to the list of devices. Is it not getting mounted properly?

What happens when you explicitly try to mount the drive?

Kirath · 09-26-2007, 12:04 PM

The problem is the device isn't created or recognized. In the log it identifies itself as /dev/sda1 right? Well...

Code:

# mount /dev/sda1
mount: can't find /dev/sda1 in /etc/fstab or /etc/mtab

Manually adding it to fstab I get

Code:

# mount /dev/sda1
mount: special device /dev/sda1 does not exist

I didn't have this problem before with Red Hat ES 4. On another system the same hardware was detected and fstab was updated automatically. I can't figure out what could possibly be different here.

farslayer · 09-26-2007, 01:05 PM

I would start by looking at the loaded modules..

Code:

it-etch:~# lsmod | grep usb
usb_storage            71840  0
scsi_mod              124168  5 sg,usb_storage,sd_mod,ahci,libata
usbhid                 37248  0
ide_core              110504  5 usb_storage,ide_generic,ide_cd,generic,atiixp
usbcore               112644  5 usb_storage,usbhid,ehci_hcd,ohci_hcd

Little things like the usb_storage module not being loaded would definitely cause problems when you try and mount the device..

Kirath · 09-26-2007, 01:18 PM

I was wondering about possible missing modules but I am still pretty new to linux.

Code:

# lsmod | grep usb    
usb_storage            60937  0
scsi_mod              125517  2 sd_mod,usb_storage

I have usb_storage loaded? (I really am guessing from output here.. like I said I'm new with this) But not something called usbcore like you do. Could this be the issue? If so how do I remedy this? And thank you for responses guys...

pcardout · 09-27-2007, 01:55 AM

Quote:

# mount /dev/sda1
mount: can't find /dev/sda1 in /etc/fstab or /etc/mtab]

You asked for places to look. The suggestion of manually mounting your
drive is a good one. Learn what it takes to do that.

The above command is inadequate because as part of mount you usually have to at least
specify the mount point and the file system. If would be something like mount /dev/sda1 /mnt/usbdrive ntfs. You can do what you did above PROVIDED you have already added
the necessary information to your fstab (that's why it complained to you about
not seeing an entry in your fstab). I'd just learn how to do it manually for now.
You can create a mountpoint just about anywhere (you might read about that).

Kirath · 09-27-2007, 05:29 AM

Thank you for the reply, but if you had read the whole thing, you would have seen I did edit the fstab, and got device does not exist. Hence it had a mount point and file system type. The problem is it keeps reporting the device does not exist. Therefore it shouldn't be surprising:

Code:

# mount -t ext3 /dev/sda1 /media/usbdisk
mount: special device /dev/sda1 does not exist

I appreciate everyone's attempts. Just really frustrated at this point.

I_like_TUX · 09-27-2007, 11:57 PM

It might not help, but it does not hurt to check:
$ ls /dev | grep sda
also, only one USB harddisk attached and no SCSI/SATA harddisk inside the box?

pcardout · 09-28-2007, 12:22 AM

You could try cfdisk /dev/sda or cfdisk /dev/sda1 to see if linux sees the drive at the lowest level. (Just don't format it!!).
I think linux does see drive based on your /var/log/messages. If drive is seen by cfdisk AND if you don't need the data on it, you could always reformat it. You gave the filesystem as ext3. The new drive probably comes with ntfs, but perhaps you have already formatted it on another Linux box?

Kirath · 09-28-2007, 07:05 AM

Quote:

Originally Posted by I_like_TUX

It might not help, but it does not hurt to check:
$ ls /dev | grep sda
also, only one USB harddisk attached and no SCSI/SATA harddisk inside the box?

Hi TUX. Thanks for the suggestion. No I already checked /dev to see if it was present, but alas, no. There is only one USB drive attached (this one that I am trying to get working again) and one internal drive:

Code:

Disk /dev/hda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Quote:

Originally Posted by pcardout

You could try cfdisk /dev/sda or cfdisk /dev/sda1 to see if linux sees the drive at the lowest level. (Just don't format it!!).
I think linux does see drive based on your /var/log/messages. If drive is seen by cfdisk AND if you don't need the data on it, you could always reformat it. You gave the filesystem as ext3. The new drive probably comes with ntfs, but perhaps you have already formatted it on another Linux box?

I actually wouldn't mind formatting this thing if I could actually get to it. It only has back-ups of the data on the internal drive. The drive was NTFS out of box, but it is formatted ext3 and it was actually done on this system. That's why this all is so weird. I can't even get to it with fdisk or anything else because you get "unable to open /dev/sda" (/dev/sda1 as well). I think if I keep banging my head against this it might start working? Heh.

pcardout · 09-28-2007, 09:27 AM

OK -- This is strange. Is beginning to sound like hardware.

I have had weird behavior with USB devices. The amount of current available on the USB bus varies with the computer and even which port
on the computer (front vs. rear). Try plugging it into different ports -- or try plugging it into a different computer and see if you can fdisk it.

pcardout · 09-28-2007, 10:00 AM

Cables break (crack, intermittent connections or high resistance
connections) -- this can cause all sorts of flakiness. Try a new
cable.

Kirath · 09-28-2007, 01:10 PM

Apparently after all this, it was udev not running for some reason that was causing this...

Code:

# mount -t ext3 /dev/sda1 /media/usbdisk
mount: special device /dev/sda1 does not exist
# /sbin/udevstart
# mount -t ext3 /dev/sda1 /media/usbdisk
# cd /media/usbdisk
# ls 
BACKUPS  documents  lost+found

I don't understand this though during bootup I do see "Starting udev [OK]" So I guess it is being stopped or crashing before GNOME boots up?I don't want to have to manually start this everytime and putting it in rc.local doesn't work.. I've seen this in a few other threads now and am working on this...anyone that might know what the problem is here on Red Hat ES4 let me know. Thanks guys...

pcardout · 09-28-2007, 01:31 PM

Nice work!! I learned something!!

I_like_TUX · 09-28-2007, 05:07 PM

I am not sure the following will work or not but you can give it a try:

1. after /sbin/udevstart, go to /dev and do:
$ ls -l | grep sda
sda, sda1, ... should be there.

2. you will see a pair of number at where the file size should be. For example, for a text file:
-rw-r--r-- ...... 512 2007-09-28 ... a_normal_file.txt
but for a device file:
brw-r----- ...... 7, 0 2007-09-27 ... sda
brw-r----- ...... 7, 1 2007-09-27 ... sda1
the 7, 0 is called major and minor number respectively, you can manually create any device node if you know the type("b" for disks), major and minor numbers. Write down the major and minor numbers you see for your own system.

3. at your (I mean root) HOME directory, type:
$ mknod usbhdd b 7 0
$ mknod usbhdd1 b 7 1
(note: 7,0; 7,1 are just for example)

4. you should be able to do:
$ mount -t ext3 ~/usbhdd1 /mnt

The /dev/sda will disappear next time you boot the system, but ~/usbhdd1 will stay since it is not in /dev. So you can try reboot the system and mount ~/usbhdd1. Please tell me if this works.