Red Hat Knowledgebase

This article assumes that you have the X Window System installed and will be using either GNOME or KDE as your graphical X Window System.

In order to disable X from loading during the boot sequence, it is recommended that you boot your system to runlevel 3. Booting your system to runlevel 3 will still allow you to log in as a system user but will provide a command line login instead of a graphical login. Once you are successfully logged in, you can then use the startx command to bring your system into graphical mode or runlevel 5:

 startx

In order to shut down GNOME or KDE, go to your Main Menu and select the "Log Out" menu option. This should shut down Xwindows and return you to a command line or runlevel 3. In order to configure your system to boot into runlevel 3, you can modify the /etc/inittab file and change the id initdefault line to runlevel 3 as shown below:

# Default runlevel. The runlevels used by RHS are:
#   0 - halt (Do NOT set initdefault to this)
#   1 - Single user mode
#   2 - Multiuser, without NFS (The same as 3, if you do not have networking)
#   3 - Full multiuser mode
#   4 - unused
#   5 - X11
#   6 - reboot (Do NOT set initdefault to this)
#
id:3:initdefault:

See additional articles in the Knowledgebase for information about changing from runlevel 3 to runlevel 5 and vice versa.