We have the following setup on several linux servers:

eth0 = Internet
eth1 = LAN (10.100.X.X)

For this example let's say we have:

eth0 goes to the internet and the default gateway is set in ifcfg-eth0
Server A has three IPs on the LAN (10.100.0.2, 10.100.22.3, 10.100.33.4)


The gateway is 10.100.9.1.

Naturally, if one IP attempts to access another IP, it is going to take the shortest path.

On Server A, the IP 10.100.0.2 attempts to access 10.100.22.3 or vice versa. We want to FORCE this traffic to go out eth1 on server A and to the gateway. The gateway is filtering traffic, so in this case we may have a rule blocking access from 10.100.0.2 to 10.100.22.3 - or perhaps a permit policy.


ip rule add from 10.100.0.2 table TEST1
ip route add 10.100.0.2 dev eth1 table TEST1
ip route add default via 10.100.9.1 table TEST1

ip rule add from 10.100.22.3 table TEST2
ip route add 10.100.22.3 table TEST2
ip route add default via 10.100.9.1 table TEST2


My understanding of source based routing tells me the above should solve the problem; however, upon adding the default gateway (ip route add default via 10.100.9.1 table TEST1 and ip route add default via 10.100.9.1 table TEST2), traffic doesn't hit the gateway at all.

Do you have any suggestions to resolve this issue - is it even possible?