echo package-name hold | sudo dpkg --set-selections
So that it will not be upgraded.
Reason: a package’s ppa has a brand new version that is not compatible with previous version, but since the new version is there so Ubuntu downloaded and installed the new version, and it made almost everything on my system broken.
Have to lock down that package, unless I’m so sure I can upgrade it.
I don’t like or dislike upstart or whatever system service management facility, however, I do hope Ubuntu can give me a single solution to handle system service.
So to disable a service, you can try System-V style:
update-rc.d apache2 disable
or upstart style:
echo manual > /etc/init/cron.override
or try chkconfig though it’s less common on Ubuntu. Sure, you may want to check /etc/rc.local as well for auto-start services that are not system service.