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Need best config to use 1720 and 2600 routers together

Unanswered Question

Previously, I had two offices connecting with 1720 routers, w/ VPN modules, across the Internet.

We just changed our ISP at one office and received

a 2600 to support dual T1 lines, one as a shadow

line, using BGP.

The 2600 doesn't have a VPN module so I want to

connect the two with a Enet WIC in order to use the

VPN module on the 1720, in which I am also using NAT.

Is the connection between the two a straight forward

Ethernet connection or does it have to use PPP?

I have working it now but I'm not sure if it's the

best config and worried about routing loops. In

addition, configuring CBAC on the 1720 in this setup

is a confusing task and I'm wondering if there isn't

a more practical solution for what I want to do.


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Georg Pauwen Mon, 12/22/2003 - 03:30
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    2017 WAN


can you post the configs of both of your routers ?



amekchompu Tue, 12/23/2003 - 05:37
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Hi Marlow,

I think behind NAT VPN will not work so you better check it. But if you can acquire some public IP address for your 1720 and place it as a VPN Gateway for your remote site it is possible solution.

Regarding your question related to connection between two routers. You can use cross UTP Cable for Router connection (PPP cost you more and give you lower speed)

Hope this help.

Currently, I am using a public address on the Ethernet0 on the 1720

and a public address on the FastEthernet0/0 on the 2600.

(Basically, x.x.x.2 on the 1720 connected to x.x.x.1 on the 2600, which then goes out to the Internet.)

Have not yet tried to setup the VPN. I only ask this question because

the Config Maker won't let me directly connect the two routers with an Ethernet

connection, even though it's physically connected this way, and was wondering if it's going

to be a problem. I've never configured any PPP connect, so I'm not familiar with them,

which led me to wonder if that's the right thing to do.

I'm going to try to setup the VPN and, hopefully, it will work fine in this setup. Thanks for your response.


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