31.5. Runlevels and X
In most cases, the Red Hat Enterprise Linux installer configures a machine to boot into a graphical login environment, known as Runlevel 5. It is possible, however, to boot into a text-only multi-user mode called Runlevel 3 and begin an X session from there.
For more information about runlevels, refer to Section 16.1, “Runlevels”.
The following subsections review how X starts up in both runlevel 3 and runlevel 5.