If you think that editing runlevels by copying symbolic links around is too arcane and error-prone, you may want to try a graphical runlevel editor. Your distribution most likely ships one, but if you have installed the KDE Desktop Environment, you probably have KSysV anyway.[*] You can start this program either from the K menu (as System Service Configuration KSysV in KDE's normal distribution) or by invoking ksysv on any command line.
If you are starting KSysV for the first time, it will ask you a few questions about your distribution so that it can determine the right location of your runlevel configuration files. Then it will show its main screen, as seen in Figure 17-1.
To the left, you can see the list of available services, and to the right of it are two lines of boxes; the upper line for entering runlevels, the lower line for leaving them. For each runlevel, one box per line is shown (unless you turn some runlevels off using the checkboxes in the status bar, which can be helpful if you only want to work on a few runlevels).
To add a service to a runlevel, simply use the mouse to drag the service name from the left to the box on the right. Don't forget to do this for both the Start and the Stop box. To remove an entry from a box, grab it and drag it to the waste bin in the lower-left corner. You can also click any entry in the runlevel boxes to configure it or to manually stop, start, or restart it immediately.
When you are done, use the menu entry File Save Configuration to save your work. This will only be allowed, however, if you have started KSysV as root, as you will otherwise not have write access to the runlevel configuration files. But if you start KSysV from within KDE, it will ask you to supply the root password anyway and switch to superuser mode.
Figure 17-1. The KSysV main window