Hello, I have a linux (2.2.X kernel) box that I am using as a firewall between my internal network and our new ADSL modem. I am currently working on configuring the ipchains on the linux box to protect my internal systems.
Question: My internal mailserver is currently running on a HP-UX C3000 which is behind the firewall (IP: 192.168.XXX.XXX). I need to configure my linux firewall to pass the SMTP transmissions to and from my server. What is the best way of doing this? Are there any additional pitfalls I should be aware of to make my systems as secure as possible? Thank you for your time! Doug Thistlethwaite
