This common task turn out to be a pain in the … if you dont know how to do it .
Ubuntu unlike other Linux distributions moved from traditional sysvinit to Upstart .
i will not name all the differences but just one fact that setting a service to run in
requiered runlevel is not done by stop/start links in /etc/rcX.d anymore, but by init scripts .
Lets start . I use lxde as my desktop and lxdm as my desktop manager ,
i would like to have no Xserver on runlevel 3 ( runlevel 2 is Ubuntu default ) .
in order to do so i edit the file /etc/init/lxdm.conf and set the runlevels i wish lxdm
to start and stop . that is done by the commands
start on runlevel [2]
stop on runlevel [0136]
start on runlevel , was not found on the script so i added it .
now lxdm will start only on runlevel 2 and would stop on runlevel 0,1,3,6
Now boot into grub entry and append the runlevl to the kernel parameters
linux /boot/vmlinuz-2.6.38-8-generic root=/dev/sda1 ro quiet 3
to make it permanently you can create a new menu entry on /boot/grub/grub.cfg
You can read more on upstart at http://upstart.ubuntu.com/index.html
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