I am using proxy arp and ip aliasing with iptables as a firewall for a few class C networks. It works with no problems. All our machines behind the firewall have public addresses. Now I would like to add a port forward rule that sends all incoming mail to another IP address. I am not sure what I'd need to do. I didn't think SNAT or DNAT were needed here as no NAT is happening. Anyone have any ideas? Do I need to mangle the destination address?
Thanks
Gareth
