Cisco 1700 Dual WAN Config 1

[jjepen]

I work at a small ISP / Repair Shop and I'm setting up a Cisco 1700 for our repair bench network. The config I've got is as follows.

Cisco 1720 with IOS v12.3
2 1ENET WICs

What I am trying to accomplish is to have the FastEthernet0 interface connected to our internal network and provide DHCP and NAT to it. Ethernet0 will be connected to a cable modem and Ethernet1 will be connected to our ISP network. I want all traffic to route out through Ethernet0 except anything that has a destination on our ISP network to route through Ethernet1. I also want it to have failover so if Ethernet0 goes down (at least twice a day it seems, damn Charter) the router will automatically switch to routing everything through Ethernet1. I've been stumped by this for a week. Any suggestions would be greatly appreciated. I have my config as it stands available if needed.

Thanks,
Jake

 

[KiscoKid]

You need to setup PBR policy based routing (PBR) with Object Tracking. It should be available for you on your version of IOS. The following link explains how to set it up:

http://www.cisco.com/en/US/tech/tk364/technologies_configuration_example09186a0080211f5c.shtml

 

[jjepen]

Thanks for the tip. Looks exactly like what I want to do.

 

[jjepen]

Well on second look the setup you suggested will not work for me. It may be an IOS version difference but basically my IOS (v12.3(13)) wants the two upstream routers to have cdp capabilities and in my setup only one will. Also it does not take into account (unless I'm reading it wrong) that I want most of the traffic to route through one interface and some through the other normally. It looks like it will route everything one way until it goes down and then failover to the other route. Thanks for the help in advance.