Am Tue, 28 Mar 2017 21:26:05 +0200 schrieb Dan Johansson <dan.johans...@dmj.nu>:
> Slight Off-topic, but at least the host are Gentoo. > > Is it possible, using iptables or something equivalent, to redirect > traffic to some specific TCP ports to another gateway than the > default-gateway? > > Eg. > > Host 192.168.1.100/24 has a default-gateway of 192.168.1.1 > Now I want to send all traffic from this host to destination-tcp-port > 80 to gateway 192.168.2.1 instead (the host has a second interface > with the address 192.168.2.100/24 as well). > I only want the traffic to port 80 to go thru this GW (and then to > its final destination). > And port 80 is just an example, it could be port 12345 as well. > > Is this possible? If yes, any suggestion on how to do it? If I understand you correctly, you want to do the redirect decision on the source machine 192.168.1.100, and not on the default gateway 192.168.1.1. This means you need to mark packages with iptables, and then doing the routing based on the mark. For this, you need to setup policy routing. Look here: http://www.tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.netfilter.html That example uses port 25 instead of 80. It marks packets, and then creates a second routing table to use for such marked packets. -- Regards, Kai Replies to list-only preferred.
