I originally wrote this as a very small tutorial for boingworld.com, which was
an Amiga/Linux/General newssite that a small group of people, including me,
ran a couple of years back. Due to the fantastic amount of readers and
comments that I got from it, I continued to write on it. The original version
was approximately 10-15 A4 pages in printed version and has since been growing
slowly but steadily. A huge amount of people has helped me out, spellchecking,
bug corrections, etc. At the time of writing this, the
https://iptables-tutorial.frozentux.net/ site has had over 600.000 unique hits
alone.
This document was written to guide you through the setup process step by step
and hopefully help you to understand some more about the iptables package. I
have based most of the stuff here on the example rc.firewall file, since I
found that example to be a good way to learn how to use iptables. I
decided to just follow the basic chain structure and from there walk
through each and one of the chains traversed and explain how the script works.
That way the tutorial is a little bit harder to follow, though this way is
more logical. Whenever you find something that's hard to understand, just come
back to this tutorial.
