| Mode | Directory | Run Level Description |
|---|
| 0 | /etc/rc.d/rc0.d | Halt |
| 1 | /etc/rc.d/rc1.d | Single-user mode |
| 2 | /etc/rc.d/rc2.d | Not used (user-definable) |
| 3 | /etc/rc.d/rc3.d | Full multi-user mode (no GUI interface) |
| 4 | /etc/rc.d/rc4.d | Not used (user-definable) |
| 5 | /etc/rc.d/rc5.d | Full multiuser mode (with GUI interface) |
| 6 | /etc/rc.d/rc6.d | Reboot |
Based on the selected runlevel, the init process then executes startup scripts located in subdirectories of the
/etc/rc.d directory. Scripts used for runlevels 0 to 6 are located in subdirectories
/etc/rc.d/rc0.d through
/etc/rc.d/rc6.d, respectively.
Determining the Default Boot runlevel
The default boot runlevel is set in the file /etc/inittab with the initdefault variable. When set to 3, the system boots up with the text interface on the VGA console; when set to 5, you get the GUI. Here is a snippet of the file (delete the initdefault line you don't need):
# 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: # Console Text Mode
id:5:initdefault: # Console GUI Mode
Note the following:
- Most home users boot up with a Windows like GUI (runlevel 5)
- Most techies will tend to boot up with a plain text-based command-line-type interface (runlevel 3)
- Changing initdefault from 3 to 5, or vice-versa, has an effect upon your next reboot. See the following section on how to get a GUI login all the time until the next reboot.
- Of course, don't set the initdefault value to 6 or your system will constantly reboot. Setting it to 0 will never allow it to start!
