Server Administration/Documenting

I'm a newbie system administrator trying to run a small email/webserver. I've managed to get everything running but I don't feel like I have a good understanding of what I did to make things work. For example, if the server was to explode tomorrow it would take me about as long to reinstall and set everything up as it did the first time.

So, my question is, how do other people document and backup their system configuration files and installation scripts. Are there tools or templates out there that help to make a single document describing all the pieces of a system? I think documenting the system will help me better understand it.

I'm using Debian and decided to install everything from source instead of using the deb packages because I wanted to have the recent versions of everything and since I know enough C to fix bugs and make changes to some of these packages I figured this way I have the ability to make updates and make them live to my users quickly. Is this a really bad idea?

Any advice from seasoned system administrators would be greatly appreciated!

Thanks a lot.

Use a backup script for debian such as:

this one
or
this one

Thanks for the backup scripts. Although they don't seem to do what I want, namely they depend on debian packages.

Actually documentaion was my biggest problem. I'm going to try to write it in LaTeX with a combination of python scripts that would gather all the needed info from the system (find all the config files and bring them into one directoy, then parse them and dump some values into LaTeX to be included in the docs).

If anyone is interested I'll keep you posted.

My main goal is to be able to produce a nice looking PDF document describing the entire system from a big pictures point of view to having the actual configs in the appendix, i would like to even include variable data like how much room is left on the harddrive and other log data. I would setup a cronjob to regenerate this document every couple of days to include any changes the system went through.