I'm seeing a lot of people giving advice to Debian users to use update-rc.d to REMOVE links for a package to prevent it from starting up. That's nice, but update-rc.d saves no state, so the next time the package is installed, all the links will be reinstalled! The correct way to disable starting of program foo is to remove /etc/rc2.d/S??foo and not through update-rc.d. If you use any other runlevels, remove the link from those as well.
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