I have built a number of NAT systems in several countries, which use
reserved IP addresses for their masqueraded networks (192.168.0.0/16,
10.10.0.0/16, etc.). I am familiar with IP tables.
Now I would like to build a system, that would just forward packets from
eth0 to eth1. Both NIC would operate in the same IP block.
That would give me an opportunity to filter out undesirables in both
directions, while making all my machines visible from outside.
I looked over HOWTO's and miniHOWTO's, but they all deal with NAT systems,
not just strict forwarding.
Before I start reinventing the wheel, I ...