How to keep apache from autostarting on system boot for Debian or Ubuntu

An easy way to remove apache2 (or another system service) from the start up scripts in Debian or Ubuntu is to use the update-rc.d mechanism.

For instance:

# update-rc.d -f apache2 remove

The “-f” is required if you have existing scripts in /etc/init.d/apache2. If you are planning on manually starting apache, the “-f” is [barring heroic/quixotic effort to create alternatives] a requirement.
Otherwise, in this situation, you will see:

update-rc.d: /etc/init.d/apache2 exists during rc.d purge (use -f to force)

A good write-up is here:
http://www.debuntu.org/how-to-manage-services-with-update-rc.d

Ubuntu 9.10 (Karmic) Beta

Instead of ‘ do-release-upgrade ‘ as I did with my upgrade to 9.04 , going to the Beta of 9.10 I used

update-manager -d

No major problems.  I did have to manually remove a couple of ppa entries from my /etc/apt/sources.list.  Also, I changed from the generic ‘main server’ to a much, much faster (at the time) server.  The easiest way to do this is via gui, as far as I know.  Ubuntu will check for the fastest responding site if you use ‘System’ -> ‘Administration’ -> ‘Software Sources’ and ‘Select Best Server’,’ or use ‘Settings’ under the update-manager interface (‘settings’ is on the lower left) to get to the same place.   I shaved off several hours from my package download by switching to a server that had some combination of proximity, light load, and high bandwidth.   This involved a generous amount of luck, and probably the uneven demand associated with a pre-release version of the OS.