what I have in my ubuntu is:
eth0(local) = 192.168.1.1/24 attemp to be gateway for local network
eth1(net1) = 192.168.2.2/24 gateway is 192.168.2.1 is a DSL 1
eth2(net2) = 192.168.3.2/24 gateway is 192.168.3.1 is a DSL 2
what I want is:
port 22,53,80,443 force to use only through eth1
port 6881 to 6889 and other ports force to use only through eth2
How to make rules in iptables?
Thank you.
Mark packages which should go via eth1:
iptables -A PREROUTING -i eth0 -t mangle -p tcp --dports 22,53,80,443 -j MARK --set-mark 1
Add rule eth1.out to route marked packages:
echo "201 eth1.out" >> /etc/iproute2/rt_tables
ip rule add fwmark 1 table eth1.out
Route all marked packages via eth1:
/sbin/ip route add default via 192.168.2.1 dev eth1 table eth1.out
Route everything else via eth2:
/sbin/ip route add default via 192.168.3.1 dev eth2
If MARK rule won't work, try using CONNMARK.