I want to run a Web server BEHIND a NAT firewall by mapping the public IP ports to the Linux server. Do I need to do anything special on the Linux side to make this work?

I have a single static IP for my ZyXEL DSL router that supports NAT + port mapping. I want to move our DNS + development Web server which currently has its own public IP over to our new network and use the port mapping to map everything over to the Linux box. This way I can use NAT for all our PCs and still run our DNS, Web, etc. by mapping them to our Linux server.

So, now for my question, I know how to map the ports on the ZyXEL router to point to my Linux server (which I have assigned 192.168.1.5 in my LAN). To enable the Linux machine as a NAT *client* (I only have a single LAN Ethernet coming into the Linux machine) do I have to do anything? Windows machines are automatic, but I doubt Linux is. I am currently running RedHat 6.1 and wondering if I need any extra modules, netconf settings, or if I just plug it in that it will work?

I am fairly certain that the port mappings will take care of the services and that the Linux box can handle requests getting routed from its public IP to its internal IP just fine. What I am not sure of is if the outbound connections will work fine (i.e. if Linux will detect the NAT gateway and use it like any other NAT PC would).

In case it matters, the services I would need are: DNS (several domains), Mail, WWW, Telnet (which we are phasing out), SSH, and FTP.

Blitzkrieg ('tanks in advance),
Christopher (chrisw@spamcop.net)
http://dq.com