You may want to permanently disable your grafical interface for some reasons. Let’s say that you want to develop new linux command line interface skills and so, you eliminate the grafical interface distraction by disabling the GUI.

The easiest way to permanently disable the grafical user interface, but to keep it installed (not to uninstall it, in case you change your mind) is to do this from the grub.
This trick works for all Linux Systems that are using Grub2 (all the new Linux Boxes use Grub2), so it is Grub dependent only.
Open your /etc/default/grub file, as root, and search for the GRUB_CMDLINE_LINUX_DEFAULT line:
$ sudo su
# grep GRUB_CMDLINE_LINUX_DEFAULT | /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
Now, make your GRUB_CMDLINE_LINUX_DEFAULT look like this (replace “quiet splash” with “text”):
GRUB_CMDLINE_LINUX_DEFAULT=”text”
Whenever you want to start the gui, use this command: sudo service lightdm start It will start you gui just this time and will not modify your grub file.