Well, it doesn't seem to be very thorough, and it wouldn't encompass non-IP (_IP_tables), but what about something like: iptables -A FORWARD -i eth0 -o ! eth1 -j LOG --log-prefix "Wrong Route: " (and -j DROP) iptables -A FORWARD -i eth2 -o ! eth3 -j LOG --log-prefix "Wrong Route: " (and -j DROP) Test this. I'm just guessing here. Bob -----Original Message----- From: netfilter-admin@xxxxxxxxxxxxxxxxxxx [mailto:netfilter-admin@xxxxxxxxxxxxxxxxxxx]On Behalf Of Ryan Johnson Sent: Monday, January 26, 2004 11:50 AM To: netfilter@xxxxxxxxxxxxxxxxxxx Subject: Firewall four nics, two separate routes Hi all, I have a firewall with four nics, two external nics with two public ips and two internal nics with private ips (two different networks). What I would like to do is force all traffic from each internal network to its corresponding external nic. I believe the only solution to this is to use iproute2, but I have had to luck. So traffic from internal net1 will be routed out external nic1, then the other side, internal net2 will be routed out the external nic2. Internal net1 traffic should never go out external nic2 and internal net2 traffic should never go out external nic1. Thank you in advance, Ryan Ryan Johnson Security Architect ESP Group
