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New Member

reroute traffic

Below is a diagram of my network. I have to locations, Atlanta and Dallas.

Both location have there own Internet Access via a T1 circuit.

Both location are connected via a dedicated T1 circuit.

All Inside nodes in Atlanta use RouterB as there default gateway.

All Inside nodes in Dallas use RouterC as there default gateway.

My question is this:

If the Atlanta Internet T1 circuit goes down, how do I configure Atlanta RouterB to identify the down circuit and reroute inside network source traffic destined for the Internet out the Dallas T1 Internet circuit via the dedicated T1?

Internet Internet

| |

|T1 |T1

| |

RouterA RouterD

| |

| |


| |

| T1 |


| |

| |

Atlanta Dallas

Inside Inside

Network Network


Re: reroute traffic

One way of accomplishing this is with floating static routes.

For example at the Atlanta site:

ip route

ip route 100 is the ip address of the Atlanta ISP is the ip address of the Dallas router

100 is the administrative distance (Atlanta will route internet traffic to the Atlanta ISP as long as it can reach the address.).

You can configure the same setup on the Dallas router in case the Dallas ISP fails.

New Member

Re: reroute traffic

I'm sorry, but your solution will not work. A static route or a floating route requires the IP address of a next-hop, which in my case for routerB is the PIX firewall (not the Atlanta ISP). And that is my problem. If the Atlanta ISP goes down, the PIX interface is still alive and therfore routerB will still send it internet traffic regardless of a floating route.

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