Having tried differen ways but none worked - How do I disable a service from auto-start at boot in Ubuntu?

view story

http://askubuntu.com – This really doesn't make sense. I've been using many other distros and never had such difficulty managing autostart services. I found three ways of disabling autostart services, and none of them works for me: update-rc.d -f service_name remove chkconfig --level 12345 service_name off sysv-rc-conf I tried all the three ways to disable mysql daemon, mongo daemon, redis server, cups daemon, yet all of the utilities confirmed that the daemons are disabled, yet they still automatically start on boot. Please suggest the most correct way to disable services from auto-start at boot. Thank you! (HowTos)