can not route packets from one interface to another
linux, networking, routes
Solution
You are missing your back path route. The host 192.168.0.2 see packet coming from 192.123.123.10 but he doesn't know how to route the reply packet back since it doesn't have the return route. You can do two things:
1- create a route on 192.168.0.2 machine to handle traffic directed to 192.123.123.0/24
2- NAT on your 192.168.0.250 host with the command below:
iptables -t nat -A POSTROUTING -s 129.123.123.0/24 -j SNAT --to-source 192.168.0.250
Problem
I have a system with 2 interfaces `eth0`, and `eth1`. - `eth0` is `192.168.0.250` and connected to gateway `192.168.0.2`. - `eth1` is connected to `192.123.123.10` via a swtich. I am trying to route packets from `192.123.123.10` to gateway `192.168.0.2`, which means I need to route `192.123.123.x` packets coming into `eth1` interface out via `eth0` interface. I set `ip_forward` file to `1`. I ran this command: ``` route add -net 192.123.0.0 netmask 255.255.255.0 dev eth0 route add default gw 192.168.0.2 ``` I can ping from `129.123.123.10` to `192.168.0.250`, but I can't ping to `192.168.0.2` I think the packets are not being forwarded to `eth0`. My routing table looks something like this: ``` gteway Genmask Flags Ref Iface 192.123.123.0 * 255.255.255.0 U eth1 192.168.0.0 * 255.255.255.0 U eth0 192.123.0.0 * 255.255.255.0 U eth0 default 192.168.0.2 0.0.0.0 UG eth0 ``` Can anyone tell me what is missing? Thank you in advance.