setting up 2 routers

BRonkBMI · 09-19-2012, 10:50 AM

I'm working on setting up a new router system for work. I'm rebuilding it from scratch because one of our boxes needs replaced anyway. We're also adding another internet provider (the main reason all this started). Right now, I'm having trouble getting them talking correctly. It seems like my ping is dropping somewhere. Here's my setup:

ServA
eth0: 192.168.144.24 (router link)
eth1: 10.198.0.1 (local network)
eth2: 10.10.10.170 (internet provider 1)

ServF
eth0: 192.168.144.50 (router link)
eth1: 10.110.0.254 (local network)
eth2: 10.50.30.34 (internet provider 2)

Both servers have ip_forwarding set to 1. Both have their iptables --flush(ed)

I know I need to get policy routing setup, so I'm starting with that. Each has 2 tables setup in /etc/iproute2/rt_tables: 200 net1 / net2, and 205 routerLink.

To setup the routes on ServA:

Code:

ip route add 10.10.10.0 dev eth2 src 10.10.10.170 table net1
ip route add default via 10.10.10.254 table net1
ip route add 192.168.144.0 dev eth0 src 192.168.144.24 table routerLink
ip route add default via 192.168.144.50 table routerLink
ip route add 10.10.10.0 dev eth2 src 10.10.10.170
ip route add 192.168.144.0 dev eth0 src 192.168.144.24
ip route add default via 10.10.10.170
ip rule add from 10.10.10.170 table net1
ip rule add from 192.168.144.24 table routerLink

To setup the routes on ServF:

Code:

ip route add 10.50.30.32 dev eth2 src 10.50.30.32 table net2
ip route add default via 10.50.30.33 table net2
ip route add 192.168.144.0 dev eth0 src 192.168.144.50 table routerLink
ip route add default via 192.168.144.24 table routerLink
ip route add 10.50.30.32 dev eth2 src 10.50.30.34
ip route add 192.168.144.0 dev eth0 src 192.168.144.50
ip route add default via 192.168.144.24
ip rule add from 10.50.30.344 table net2
ip rule add from 192.168.144.50 table routerLink

The provider on ServA should handle all traffic by default. That's why I have default traffic for ServF going to the router link.

ServA can connect to the internet right now with no issues. I'm having a problem with ServF. I can ping 192.168.144.24 and 10.198.0.1 on ServA and get replies. When I try to ping 10.10.10.170, I get nothing. Using tcpdump, I see the packet going into ServA via the router link. I don't see any traffic on eth2 related to that ping. It seems like it's dropping off somewhere, but I don't know where.

Any help getting this working would be appreciated. Thanks all.

BRonkBMI · 09-19-2012, 01:38 PM

I solved part of this. I can now ping ServA: 10.10.10.170 from ServF. I removed the "ip rule from" lines from both servers. Can someone explain why this is?

My end result would be to have traffic that comes from either internet provider go back out the way it came in, hence the rules. I verified that it was the net1 and net2 rules (specifically net1 in this case) that caused the problem. But, I'll need those rules for policy routing, right?

In the mean time, forging ahead with getting ServF able to see the internet. I think I know the next step for that, at least.