how many runlevels are there in Ubuntu

[Alan Mckinnon]

On Thu, 2006-08-10 at 16:39 -0400, Qiuli Han wrote:
> Hi list
> i noticed that the ubuntu run levels are different from the standard
> linux, there is no run level 5 and 2 is the X. so what are the run
> levels in ubuntu?

I think you are assuming that the Red Hat way of doing things is somehow
a "standard". This is not true, it's only one way of doing it.

Ubuntu, being Debian-based, doesn't do things the way Red Hat and
derivatives do. All 10 runlevels in Sys V init are there
(0,1,2,3,4,5,6,s,a and one other which I forget) but only four are
effectively used - 0, 1, 2 and 6.

Think about this: the machine is either starting up, shutting down, in
single user mode for maintenance, or in regular use. Regular use is
runlevel 2. If you want a gui, you configure it to start a display
manager. If you don't want a gui, then don't start a display manager. To
do the equivalent to the RH thing of going to runlevel 3 for 5, just
kill xdm.

You can of course manually define runlevels 3 - 5 to have any
configuration you wish and use them as you please.

alan