How to enable non-root user to mount partitions on usb device

By default non root user can not auto mount an external USB drive partition. To allow non-root user to mount external USB drive partition you should do the following:

• add the user name to group plugdev (edit /etc/group)
• edit /etc/login.defs and add to the line with CONSOLE_GROUPS the group plugdev
• logout and login

assuming that user name is “xyzt2″ then your /etc/group file will look similar to this:

root@magelan:/home/xyzt2# cat /etc/group | grep xyzt2
wheel:x:10:root,xyzt2
audio:x:17:xyzt2
cdrom:x:19:xyzt2
plugdev:x:83:xyzt2

and /etc/login.defs will have the line

CONSOLE_GROUPS         floppy:audio:cdrom:video:scanner:plugdev

What I usually do is also to give rights to this user to mount the cdrom also

Where is the mount point

use command “mount” in the console to see where the partition is mountedusually it is under directory /media and the name of the mount point is the volume label of the partition for exampel

mount
...
/dev/sdb6 on /media/ntfs320 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096,default_permissions)
/dev/sdb1 on /media/disk type reiserfs (rw,nosuid,nodev,uhelper=hal)

Adding permanent entry in /etc/fstab

Another thing which is important to explain here is that /etc/fstab is also important. Lets assume that you have several partitions on your usb drive. For example:

root@magelan:/home/xyzt2# fdisk -l /dev/sdb
...
Device Boot      Start         End      Blocks   Id  System
/dev/sdb1              63    40017914    20008926   83  Linux
/dev/sdb2        40017915   100036754    30009420   83  Linux
/dev/sdb3   *   100036755   160055594    30009420   af  HFS / HFS+
/dev/sdb4       160055595   625137344   232540875    5  Extended
/dev/sdb5       239995098   474383384   117194143+   c  W95 FAT32 (LBA)
/dev/sdb6       474383448   625137344    75376948+   7  HPFS/NTFS/exFAT
/dev/sdb7       160055658   168055964     4000153+  82  Linux swap
/dev/sdb8       168056028   239995034    35969503+  83  Linux
...

and you have a line in your /etc/fstab like this:

/dev/sdb5      /mnt/dos320     vfat    uid=1000    0 0

What will happen is that you will not be able to auto mount partition /dev/sdb5 but you will be able to auto mount all other partitions like this one /dev/sdb6. The error that you will see in KDE will be:
“mount: only root can mount /dev/sdb5 on /mnt/dos320″.

What you should do is to add options “user” to the /etc/fstab entry for that partition. And your /etc/fstab will look like this:

/dev/sdb5       /mnt/dos320     vfat    uid=1000,user    0 0