zak317 posted this from /etc/inittab. It explains what each run level is - 3 is everything running except X windows, 5 is to run X-Windows on startup as well. Your run level 3 shouldn't be starting X up. Also don't fiddle with the files and symlinks in the /etc/rc.* directories - use either chkconfig from the command line as root or Fedora's Services config GUI (in System Tools in the menu or run system-config-services).

My problem is that I have use the tool " system-config-services" to configure the three run level 3, 4 and 5 to start the same services. So I think these three run level must be the same so, why only five work, 3 and 4 doesn't

]

No that's not what I meant I'm saying that your system is setup correctly already - the X windows services (xfs, dm etc.) should only start up in runlevel 5. What I meant was that in future you should use chkconfig or system-config-services to enable or disable services that you don't want to startup. When you enable or disable services using one of these programs they make sure to enable/disable things in the correct runlevels. In other words you should not
a) Edit the stuff in the rc.* files directly unless you really know what you are doing
b) Try and make runlevels the same - this is not how the system is supposed to work and you will likely end up with an unbootable or buggy/unstable system if you fiddle with this stuff.

Have you changed the default runlevel to 5 in /etc/inittab (as zak317 said) and rebooted? If you've done this and it hasn't worked then its most likely a problem with X windows. Try running system-config-display again or post back here for help getting it working.

Thanks for all of your help guys. My system is working now.
BUT I want to ask for these issues:



I have tried to use the system-config-services to make run level 3 start X windows automatically like run level 5.
I have check enables all of the services, which is enabled in run level 5, to start in run level 3 . So, Why run level 3 didn't work?
Because run level 4 is unused so, I want to turn run level 4 into the same as run level as a reserved so that if run level 5 is broken I can use run level 4 instead but run level 4 is not work too,Why?

No that's what I mean - DO NOT try and make runlevel 3 the same as 5. This is wrong. Runlevel 3 is the mode you put the system in when you don't want X windows, runlevel 5 is the mode you put the system in when you do want X windows. Its simple as that - it doesn't require you to fiddle around with the runlevels. The system-config-services thing is for enabling/disabling services and it will automatically determine what runlevels to enable/disable them in - usually 2,3,4 and 5.

You might want to read up a bit on how the SysV Init stuff works:
http://www.redhat.com/docs/manuals/l...down-sysv.html

So, I should not try to make run level the same as 5. But run level 2 and 4 is empty. But, how can I make run level 2 and 4 the same as 5 so if I destroy run level 5, I can use the run level 2 and 4 instead

You don't need to change anything with the runlevels. There is no way that you will 'break' runlevel 5 if you enable/disable services with chkconfig or system-config-services. One of the reasons these programs were written is so you don't have to edit the symlinks and files in the rc.* directories, which could lead to errors. Trying to make one of the other runlevels the same as 5 is pointless and could easily lead to errors if you do something wrong.

You can have only one run level at a time. The runlevel determines how the computer boots
I think you might be looking for both the gui (graphical user interface) and a virtual console (which I think you are calling runlevel 3). To access those, stay at runlevel 5 and press alt+ctrl+f1, the other function keys ie, alt+ctrl+f1-6 should work also. Your gui is on alt+ctrl+f7
the best of both worlds!! Happy computing, Kurt