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2 Site Point-to-Point T1 with Internet Access

jeremy95926 asked
Last Modified: 2010-04-17
We have two sites that currently connect to each other over the internet with a VPN. Each site has their own T1 to the internet. We have ordered a point-to-point T1 to give us better speed and reliability between sites. Both sites use public IP's with full class-C addresses. I've never setup a cisco router to make such routing choices:

Site 1 Net --> 172x cisco --> firewall --> T1 Internet Router --> Internet
                                                                     Point-to-Point T1
Site 2 Net --> 172x cisco --> firewall --> T1 Internet Router --> Internet

At minimum we would like to have the 172x's route through the private line traffic destined for the other site and through the firewall if it is for any other network. Ideally, the 172x's would failover to the firewall if the private line were down. Some help with the configs would be really great.

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Top Expert 2009
This one is on us!
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Just to make sure you are clear on my setup and I understand your response. Two things:
1) the firewall is separate hw from the cisco
2) if I understand what you are saying...I'm making it harder than it really is. If I place the cisco in the network as I've shown in the diagram above. Make sure it is working w/o the serial p-2-p as desired with default route to the firewall. Thensetup the Cisco to handle the p-2-p over the serial as you normally would. Add a route to the other site with serial ip of the other site and traffic will route as desired and it will have redundancy too.

Did I get that right?
Les MooreSystems Architect
Top Expert 2008

Sounds right.
The real key is that this router, and not the firewall, is the default gateway for all the local LAN clients and servers.
Top Expert 2009

Yes, that is right.
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