Linux route command. Two gatways on the same subnet range

Question

I have a Linux box with two interfaces.
eth0 has ip 192.168.71.82/255.255.252.0
eth1 has ip 192.168.4.2/255.255.255.0
I need all traffic for subnets 192.168.4.0/24 192.168.3.0/24 192.168.2.0/24 to go through eth1 and all the rest to go through eth0.
Which is the best way to do this?
route command?
Cheers for the help.

none of those work im asking the same question here https://unix.stackexchange.com/questions/614201/linux-add-static-route-simple-works-on-windows-not-on-linux — user3265051, Oct 12 '20 at 22:18

score 4 · Accepted Answer · answered Jul 08 '13 at 12:04

4

Just set routes to your desired Networks over eth1:

route add -net 192.168.4.0 netmask 255.255.255.0 dev eth1
route add -net .........

And then set your default gateway to whatever you need:

route add default dev eth0

(Nevertheless a route using an interface looks a bit strange to me - usually you should address the gateways using the correct router(s):

route add -net 192.168.3.0 netmask 255.255.255.0 gw <your routers IP>

answered Jul 08 '13 at 12:04

Pascal Schmiel

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route add -net 192.168.3.0 netmask 255.255.255.0 gw worked like a charm. Cheers for the help. How would I go about making the changes stick after reboot on a Debian based distro? – user2284355 Jul 08 '13 at 12:22
1

You can add commands in /etc/network/interfaces that should be executed after the interface is up using the keyowrkd "up" in your interface section. F.e.: "up route add -net ......." – Pascal Schmiel Jul 08 '13 at 12:39

score 1 · Answer 2 · answered Jul 08 '13 at 12:04

route add default gw <eth0 gateway> dev eth0
route add 192.168.4.0 netmask 255.255.255.0 gw <eth1 gateway> dev eth1
route add 192.168.3.0 netmask 255.255.255.0 gw <eth1 gateway> dev eth1
route add 192.168.2.0 netmask 255.255.255.0 gw <eth1 gateway> dev eth1

That ought to do it.

Linux route command. Two gatways on the same subnet range

2 Answers2