I recently moved from Ubuntu 14.10 to Debian Testing. Under Ubuntu I had a shell script for backing up my home folder to a USB stick. The last line of the script unmounts the USB stick. Adapting it to Debian's file system, it should be:umount /media/usb0(or umount /media/usb which links to /media/usb0). But when I execute the script, this last line throws umount: /media/usb0: umount failed: Operation not permitted. Obviously, with sudo it works, but I'm wondering why I need to be sudo here (was not necessary on Ubuntu). Any ideas how to circumvent that, so how to unmount the USB stick without being root? (the remaining part of the script runs flawlessly). UpdateThis is my /etc/fstab:# <file system> <mount point>   <type>  <options>       <dump>  <pass>/dev/mapper/sklar--vg-root /               ext4    errors=remount-ro 0       1# /boot was on /dev/sda1 during installationUUID=a90bee04-e08a-4a86-8465-762aca5719a4 /boot           ext2    defaults        0       2/dev/mapper/sklar--vg-swap_1 none            swap    sw              0       0/dev/sdb1       /media/usb0     auto    rw,user,noauto  0       0
Debian: umount /media/usb0: Operation not permitted
debian;shell script;mount;unmounting
By default, mount is only allowed for root, or, if specified in /etc/fstab, by users.Now, if you USB drive is auto-mounted without being specified in /etc/fstab (or manually by root), will not be mounted with user=youruser option, so youruser will be unable to umount it.If your USB drive is specified in /etc/fstab with user option, any user will be able to mount it, and the same user (and root) will be able to umount it.What you need, is for your USB drive to be specified in /etc/fstab, with user=youruser. In that case, no matter if root or youruser mounts the USB drive, youruser will be able to umount it.