Asymetric Routing Problem

Unanswered Question
Feb 8th, 2008
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I have two Routers connected with Two different ISP. Both connected with Layer 3 switch. I have applied Policy base routing on layer switch. Now when switch sending few subnets towards ISP B and few subnets are going to ISP A.

But problem is that, my traffic goes to ISP B is fine, but it is coming back via ISP A link. means ASYMERTRIC ROuting is occuring.

I want to have configuration in which same return path use, which used for out going.

Can anyone provide me with the configuration. I am using static routes.

Layer 3 swith has defualt route towards ISP A and for ISP B using route map.

I have also attached the network diagram for review. Kindly see it and help me out.

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royalblues Fri, 02/08/2008 - 04:46
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Since you mention that you have 2 different ISPs and they both are accepting your prefixes, you would be mostly be owning them

In that case you can run BGP and use AS-Prepend for manipulating the incoming traffic. You can ask your service provider to send just the default route downstream




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