Routing Problem

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Mar 9th, 2007
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Dear ALL

There is a problem that i am facing on a 3745 router. there is one wic-adsl card for connecting the internet which is working fine, recently a leased line with static ip has been brought from the isp. The problem is this that when the lease line inter face (SERIAL INT) is up the users lose the internet connectivity because all the traffic gets routed to serial int(static ip) rather then adsl(dynamic IP).

i tried chaning the routes but its not working out can some one please help me in this regard


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ahmednaas Fri, 03/09/2007 - 00:14
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Please post your current config and your topology.

And what is the purpose of the leased line? To connect to a remote site?

aamirdhedhi Sat, 03/10/2007 - 05:47
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Dear Ahmed i have attached the show run and show ip route and show ip int brie details

in show ip route there is one with serial interfface up and one is with serial int down


ahmednaas Sat, 03/10/2007 - 09:00
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Where does the serial line go to? Do you really need to have a default route pointing to it? If it is going to another branch office you should route only relevant traffic to it.

Also you do not need to route to both ATM0/0, and dialer1. Routing to dialer1 is enough. Maybe you can have something like:

ip route x.x.x.x m.m.m.m serial0/1 (only relevant traffic)

ip route dialer1 (the rest goes here)

aamirdhedhi Sat, 03/10/2007 - 11:32
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this serial link is between office in US and dxb and application will be used through this interface

what do u mean by m.m.m.m

ahmednaas Sat, 03/10/2007 - 11:54
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By that I mean the network (x.x.x.x) at the far end of the serial and its mask (m.m.m.m).

aamirdhedhi Sun, 03/11/2007 - 10:45
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Dear Ahmed i tried doing what u just said but still no use

the serial int ip is and the isp gateway is

same thing is happening when i define the route ip route int s0/1.

do u think that policy based routing will help ???

ahmednaas Sun, 03/11/2007 - 11:11
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let us suppose you have this network on your remote office: then you should have:

ip route

ip route dialer1

in this case the traffic that matches the specific route (traffic to your remote site) will be sent using serial0/1. All other traffic will be sent over the default route (ADSL).

And of course, you can use PBR to accomplish the same task.

aamirdhedhi Sun, 03/11/2007 - 12:07
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Thanks Ahmed for your prompt response i will try this once i get to the client site tomorrow, one more thing the isp has also provided the client with 5 more useable ip addresses 128 to 133 where x.x.x.133 is ther serial interface ip address. how will the users be able to communicate with the current setup. do i need more nat on the router.


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