Linux Firewall and NAT for DSL

Support for Home LAN (Masquerading) and for Servers in Demilitarized Zone(DNAT)

by Jan K. Labanowski, jkl@ccl.net


Location: http://www.ccl.net/cca/software/UNIX/netfilter

I was using RoadRunner (a cable modem) for a long time, and created a setup to use only one Dynamic IP address (DHCP) and have several computers attached to it at home. It uses iptables (netfilter) which comes with new Linux 2.4 kernel. I use RedHat Linux distribution, but you can easily do the same with other excellent Linux distros. I call this setup my HOME LAN. It is now a history for me, but it worked quite well (even for my neighbor). This setup is described here:

HOME LAN and INTERNET ACCESS WITH ONE DYNAMIC IP ADDRESS

 http://www.ccl.net/cca/software/UNIX/netfilter/home_lan/

Then I decided to switch to DSL and got myself a static addresses and have my own Web server, ftp servers, and DNSes, and stuff. So I made a nicer script which supports not only the HOME LAN, but also supports multiple static IP addresses, Destination Network Address Translation (DNAT), and is very easy to customize even for a non-technical person. I was able to abstract the firewall rules into a small table, which can be just edited by hand in a very localized place in the iptables script. I still do not have a write-up on my DNS setup, but it will be coming one day.

HOME LAN and DMZ FOR SERVERS WITH SEVERAL STATIC IP ADDRESSES

 http://www.ccl.net/cca/software/UNIX/netfilter/lan_and_dmz/

Please help me fix the bugs and problmes which you see with these files, so they are useful. Just send me e-mail to jkl@ccl.net

Thanks
Jan Labanowski, jkl@ccl.net