Disable services on boot – Ubuntu 12.04

 You can install Boot-Up Manager from Ubuntu software center to enable or disable services on start up.

sudo apt-get install bum


or
 
To keep my desktop (notebook) machine light and responsive I don’t want unnecessary services starting on boot-time. Turns out Ubuntu is surprisingly cumbersome to configure in this area (compared to RedHat / Fedora).
Two services I need on my notebook, but don’t want them to start unless I require them running are MySQL and Apache. But it looks like some services are started using upstart init daemon and it appears there is no management tool for this. Services can pe prevented from auto-starting either by renaming the config file or commenting out the start line in the config file
sudo cp /etc/init/mysql.conf /etc/init/mysql.conf.modified
sudo rm /etc/init/mysql.conf
Or comment out the following line in the config file
sudo vim /etc/init/mysql.conf
#start on runlevel [2345]
Reference: http://upstart.ubuntu.com/cookbook/#disabling-a-job-from-automatically-starting
Other services are still started using rc.d such as Apache. They can be disabled using
sudo update-rc.d -f apache2 disable
Now these services should not start up when the machine boots and can be started manually
sudo service apache2 start
sudo service mysql start