IP Address Aliasing (more than one IP address)

[gtmtnbiker98]

I am getting ready to setup a firestarter firewall as a perimeter (gateway) firewall. I need to add more than one IP address to the external interface so that I can port forward from these external IP's to internal IP's.

For example external 23.145.165.134 port:80 to internal 192.168.0.3
For example external 23.145.165.135 port:25 to internal 192.168.0.40
For example external 23.145.165.135 port:80 to internal 192.168.0.23

So, what I'm asking is how to assign multiple IP addresses to the same NIC. I will be using CentOS 4.3 and Firestarter as the firewall. Is this possible or is there a better firewall application out there. I'm looking for simplicity and reliability.

TIA

[forgottentq]

It's actually extremely easy to do this.. Each device is registered by number right? eth0, eth1, eth2 etc.. Well each interface has it's own inet numbering system. All you have to do is configure eth0 with your primary ip.. then eth0:1 with another ip eth0:2 with another, so on and so forth.