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mount error for external usb ext3 drive: device not found

Hi,
I am having trouble to mount this external drive both as sudo and as root. This drive is formatted to ext3, and the system is CentOS 5. I remember mounitng similar drives in similar fasion in this machine. But I do not understand what is going wrong this time. Here are my results of fdisk and mount command:

Code:

somesh@archean media$ sudo /sbin/fdisk -l



Disk /dev/sda: 300.0 GB, 300000000000 bytes

255 heads, 63 sectors/track, 36472 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes



  Device Boot      Start        End      Blocks  Id  System

/dev/sda1  *          1          25      200781  83  Linux

/dev/sda2              26        2065    16386300  82  Linux swap / Solaris

/dev/sda3            2066        3977    15358140  83  Linux

/dev/sda4            3978      36472  261016087+  5  Extended

/dev/sda5            3978        4614    5116671  83  Linux

/dev/sda6            4615      36472  255899353+  83  Linux



Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes

255 heads, 63 sectors/track, 121601 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes



  Device Boot      Start        End      Blocks  Id  System

/dev/sdc1              1      121601  976760001  83  Linux

somesh@archean media$ sudo mount -t ext3 /dev/sdc1 USB_Bkup/

mount: special device /dev/sdc1 does not exist

The sudoers file is:

Code:

## Sudoers allows particular users to run various commands as

## the root user, without needing the root password.

...

## Mount

Cmnd_Alias MOUNT = /sbin/fdisk, /sbin/sfdisk, /bin/mount, /bin/umount

...

%group.sudo-all    ALL=(ALL)      ALL

%access.workstations ALL=NOPASSWD:MOUNT

I am member of both group.sudo-all and access.workstations groups.
And this is the fstab file:

Code:

-bash-3.2# cat /etc/fstab

LABEL=/                /                      ext3    defaults        1 1

LABEL=/scratch          /scratch                ext3    defaults        1 2

LABEL=/var              /var                    ext3    defaults        1 2

LABEL=/boot            /boot                  ext3    defaults        1 2

tmpfs                  /dev/shm                tmpfs  defaults        0 0

devpts                  /dev/pts                devpts  gid=5,mode=620  0 0

sysfs                  /sys                    sysfs  defaults        0 0

proc                    /proc                  proc    defaults        0 0

LABEL=SWAP-sda2        swap                    swap    defaults        0 0

#LABEL=Bkup      /media/USB_Bkup        fuseblk rw,suid,dev,noexec,noauto,user,async,dmask=000,fmask=111        0 0

#LABEL=SAMSUNG          /media/USB_Bkup        vfat    rw,suid,dev,noexec,noauto,user,async,dmask=000,fmask=111        0 0

#/dev/Bkup              /media/USB_Bkup        vfat    rw,suid,dev,noexec,noauto,user,async,dmask=000,fmask=111        0 0

#LABEL=Elements                /media/Elements        fuseblk user,defaults 0 0

#/dev/sdb1              /media/Elements        fuseblk rw,suid,dev,noexec,noauto,user,async,dmask=000,fmask=111        0 0

#/dev/sdb1              /media/Elements        ext3    defaults 0 0

#LABEL=USB                /media/Elements        ext3    rw,noexec,noauto,user,async    0 0

#/dev/sdb1              /media/Elements        ext2    rw,pamconsole,fscontext=system_u:object_r:removable_t,exec,noauto,managed 0 0

I had issued a mount -a command to make sure this fstab is loaded.
Any clue?
TIA,

Code:

vgdisplay

Try this command.

You might have to do this as well... to find the volume group on the disk.

Code:

vgscan

Quote:

Originally Posted by szboardstretcher (Post 4291637)

Code:

vgdisplay

Try this command.

You might have to do this as well... to find the volume group on the disk.

Code:

vgscan

Still nothing. Actually vgdisplay and vgscan shows nothing!

Code:

-bash-3.2# vgdisplay -v

    Finding all volume groups

-bash-3.2# vgscan

  Reading all physical volumes.  This may take a while...

-bash-3.2# vgdisplay -v

    Finding all volume groups

-bash-3.2# fdisk -l



Disk /dev/sda: 300.0 GB, 300000000000 bytes

255 heads, 63 sectors/track, 36472 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes



  Device Boot      Start        End      Blocks  Id  System

/dev/sda1  *          1          25      200781  83  Linux

/dev/sda2              26        2065    16386300  82  Linux swap / Solaris

/dev/sda3            2066        3977    15358140  83  Linux

/dev/sda4            3978      36472  261016087+  5  Extended

/dev/sda5            3978        4614    5116671  83  Linux

/dev/sda6            4615      36472  255899353+  83  Linux



Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes

255 heads, 63 sectors/track, 121601 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes



  Device Boot      Start        End      Blocks  Id  System

/dev/sdc1              1      121601  976760001  83  Linux

-bash-3.2# mount -t ext3 /dev/sdc1 /media/USB_Bkup

mount: special device /dev/sdc1 does not exist

Code:

ls -alh /dev/sdc*



file /dev/sdc1



dmesg | grep sdc



lsusb

Quote:

Originally Posted by szboardstretcher (Post 4291649)

Code:

ls -alh /dev/sdc*



file /dev/sdc1



dmesg | grep sdc



lsusb

There is no entry for /dev/sdc1

Code:

-bash-3.2# ls -alh /dev/sdc*

brw-r----- 1 root disk 8, 32 Mar 15 12:43 /dev/sdc

-bash-3.2# file /dev/sdc1

/dev/sdc1: ERROR: cannot open `/dev/sdc1' (No such file or directory)

This lead me to do this:

Code:

-bash-3.2# ls -alhrt /dev/* | tail -n 30 

crw-------  1 root root 13, 67 Feb 21 09:39 event3

drwxr-xr-x  2 root root    200 Feb 21 09:39 .

drwxr-xr-x 13 root root  4.5K Mar 15 12:43 ..



/dev/cpu:

total 0

drwxr-xr-x  2 root root  80 Feb 21 09:39 6

drwxr-xr-x  2 root root  80 Feb 21 09:39 7

drwxr-xr-x  2 root root  80 Feb 21 09:39 4

drwxr-xr-x  2 root root  80 Feb 21 09:39 3

drwxr-xr-x  2 root root  80 Feb 21 09:39 5

drwxr-xr-x  2 root root  80 Feb 21 09:39 2

drwxr-xr-x  2 root root  80 Feb 21 09:39 1

drwxr-xr-x  2 root root  80 Feb 21 09:39 0

drwxr-xr-x 10 root root  200 Feb 21 09:39 .

drwxr-xr-x 13 root root 4.5K Mar 15 12:43 ..



/dev/shm:

total 12K

-rw-rw-rw-  1 somesh somesh  16 Feb 22 12:00 sem.ADBE_WritePrefs_somesh

-rw-rw-rw-  1 somesh somesh  16 Feb 22 12:00 sem.ADBE_REL_somesh

-rw-rw-rw-  1 somesh somesh  16 Feb 22 12:00 sem.ADBE_ReadPrefs_somesh

drwxrwxrwt  2 root  root    100 Feb 22 12:00 .

drwxr-xr-x 13 root  root  4.5K Mar 15 12:43 ..



/dev/usbdevices:

total 0

lrwxrwxrwx  1 root root    7 Mar 15 12:43 samsung1tb -> ../Bkup

drwxr-xr-x 13 root root 4.5K Mar 15 12:43 ..

drwxr-xr-x  2 root root  60 Mar 15 12:43 .

Looking at the dates, I then issued this mount command:

Code:

mount -t ext3 /dev/usbdevices/samsung1tb /media/USB_Bkup

and voila! It worked.

But that brings the question that why fdisk is showing something when that is not correct. Also why does this usb device going to /dev/usbdevices/samsung1tb ?
FYI, I tried various automount options with this drive in this machine long ago using udev and label. And some of them worked, before I switched to sudo based mounting! Now I have commented out all such commands in fstab. Also I formatted this drive from NTFS to EXT3 just an hour ago!
So why is fdisk is pointing at something else?

TIA,

Here are the output of dmesg and lsusb:

Code:

-bash-3.2# dmesg | grep sdc

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 13:0:0:0: Attached scsi disk sdc

SCSI device sdc: 3905656832 512-byte hdwr sectors (1999696 MB)

sdc: Write Protect is off

sdc: Mode Sense: 23 00 10 00

sdc: assuming drive cache: write through

SCSI device sdc: 3905656832 512-byte hdwr sectors (1999696 MB)

sdc: Write Protect is off

sdc: Mode Sense: 23 00 10 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 17:0:0:0: Attached scsi disk sdc

EXT3 FS on sdc1, internal journal

SCSI device sdc: 4012032 512-byte hdwr sectors (2054 MB)

sdc: Write Protect is off

sdc: Mode Sense: 23 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 4012032 512-byte hdwr sectors (2054 MB)

sdc: Write Protect is off

sdc: Mode Sense: 23 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 23:0:0:0: Attached scsi removable disk sdc

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 25:0:0:0: Attached scsi disk sdc

VFS: Can't find a valid FAT filesystem on dev sdc1.

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 26:0:0:0: Attached scsi disk sdc

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 27:0:0:0: Attached scsi disk sdc

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 28:0:0:0: Attached scsi disk sdc

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 29:0:0:0: Attached scsi disk sdc

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

SCSI device sdc: 1953525168 512-byte hdwr sectors (1000205 MB)

sdc: Write Protect is off

sdc: Mode Sense: 28 00 00 00

sdc: assuming drive cache: write through

 sdc: sdc1

sd 30:0:0:0: Attached scsi disk sdc

EXT3 FS on sdc1, internal journal

EXT3 FS on sdc1, internal journal

-bash-3.2#

-bash-3.2#

-bash-3.2# lsusb

Bus 004 Device 001: ID 0000:0000  

Bus 004 Device 002: ID 413c:1004 Dell Computer Corp. 

Bus 004 Device 003: ID 413c:2006 Dell Computer Corp. 

Bus 003 Device 002: ID 046d:c045 Logitech, Inc. Optical Mouse

Bus 003 Device 001: ID 0000:0000  

Bus 002 Device 001: ID 0000:0000  

Bus 001 Device 027: ID 04e8:5f05 Samsung Electronics Co., Ltd 

Bus 001 Device 001: ID 0000:0000  

Bus 005 Device 001: ID 0000:0000