Disabling startup of a service in Ubuntu

Sometimes is not easy to solve easy problems.
Today, after some research, I found how disable service in Ubuntu… It’s better to fix that, instead to lose more time in a near future.
To disable a service in Ubuntu it’s necessary remove the symlinks from all the runlevel-specific directories, /etc/rc*.d. The command to do that is update-rc.d.
ubuntu# update-rc.d -f openvpn remove