I have two ADSL routers with different providers connected to different phone lines to the internet. These routers have addresses 192.168.0.1 (home traffic) and 192.168.1.1 (business traffic) on my local network and are connected to my CentOS box.

eth0 10.0.0.2 # home LAN
eth1 192.168.0.2 # home interface
eth2 192.168.1.2 # business interface

I want some computers on my home LAN with address say from 10.0.0.50-10.0.0.60 to be routed through the 192.168.1.1 gateway, and computers with addresses > 10.0.0.60 to be routed through the 192.168.0.1 gateway. I also want to let 10.0.0.50 to communicate with 10.0.0.61,etc (file sharing, remote desktop, etc)

I am using shorewall to configure iptables and squid as a transparent proxy. Is my configuration possible? How should I do it? I know that I need to look at routing tables or somesuch but am a little daunted by the prospect. Anyone willing to hold my hand through this process?

http://www.linuxhorizon.ro/iproute2.html

nothing more to say...