Re: Dual Network/Internet Connection - Advanced Routing

[Steve Holdoway]

Kim Robertson wrote:
Hi,
Ok the subject is a little misleading, what I am looking to do is have 
an internet connection on one ethernet card, an external network on 
another card and the internal network on yet another card.
                          ----------------------
                          |                           | --------- 
External Network
Internal---------|   Linux Box      |
                          |                           | --------- 
Internet
                          ----------------------
The external network has 2 set address ranges lets call them 172.x.x.x 
and 173.x.x.x
I want the traffic on those to ranges to go via the External Network 
NIC and all other to go via the Internet
So far researching on how to do this it looks link I need to use 
iptables and do some advanced routing.

Currently I am experimenting with slackware 10.1 as the base, but if 
another dist is better I will get it.
Can anyone point me in the right direction or give me some pointers/help?

Thanks,
From Kim
To start with I'd get the routing working, and set the default route up 
to be the internet interface, and then set static routes up for 172.x 
and 173.x to your other nic.

I'd add the following lines to /etc/init.d/networking, but that's where 
slackware differs ):

/sbin/route add -net 172.0.0.0/8 gw x.x.x.x
/sbin/route add -net 173.0.0.0/8 gw x.x.x.x
Once that's working, then play with the firewalling.
Good luck,
Steve