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Dial backup Router

My network...

My wide area network is connected through leased line from main office to remote side, as contingency to the connection setup I use the Async serial ports of a router (2500) to dial up whenever the leased line is down whereas to re established a connection to the main office, however due to the limited ports availability within my dial backup router (Cisco 3640) i need to setup another router that will work in a situation where the existing Cisco 3640 could no longer accommodate the volume of my downed remote users (more than 16 dial back up lines in my case)...

The problem...

The problem is the remote users that use the 2500 routers could not accomodate secondary dialer map ip in its async interface it only accept one (1), I want the router to dial another numbers setup to the secondary backup just in case the first dial backup router failed to provide its services.

I dont know if there is a solution to this problem or if there's another work around that could help me to resolve my problem...

I'm trying to run this expansion setup, because the 3640 was setup first with 16 dial backup lines 4 years ago, now i'm adding another dial backup to support the existing 3640.



Re: Dial backup Router

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Re: Dial backup Router

This can be solved if you are willing to "cheat" on IP addressing. Use IP unnumbered on the dial in interfaces on the called routers using a loopback address with the same IP address on both routers (make sure you have a loopback with a numerically higher IP address which is unique on each router, or you can break EIGRP, OSPF and other protocols which use the highest loopback IP to identify the router). You can then treat both core routers as alternate numbers for the same dialer group, so you only need to put in multiple dialer maps or dialer strings with the different phone numbers to use.

There are more details and configuration examples in the Hub and Spokes chapter of my book High Availability Networking with Cisco, plus the configuration examples from the book are on my web site. Good luck and have fun!

Vincent C Jones

New Member

Re: Dial backup Router

Hi leonardo

Exactly I am not getting your problem but Ican suggest one solution if I am understanding that your remote site is using 2500 router to dial out. There is one command " dialer order .

I think this command is available in IOS version 12.1.

Otherwise you can use dilaler rotary group at your 3600 main branch side.So when one number is busy call will go on another.

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