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Re: BGP weight posted 11/06/2008
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I'm not exactly sure what you're trying to do in this scenario.  Weight is
locally significant only.  It seems as though if you want to choose routes
from one path over another by means of using Weight in AS2 you'd want to
apply your weight values on R4.  A numerically higher weight (more
preferred) for the routes learned via either R2 or R3.

Jason

On Wed, Nov 5, 2008 at 10:08 PM, stephen skinner <stephenski@xxxxxxxxx>wrote:

> Hello ,
> can i ask a quick question please
>
> My topology
>
>   R1
>  |     |
> R2   R3
>   |   |
>   R4
>
> R1 is in AS1
> R2,R3,R4 are in AS2
>
> R1 peers to R2 and R3
> R2 and R3 peer to R4
>
> router-id are 1.1.1.1 -  2.2.2.3 -  3.3.3.3 - 4.4.4.4
>
> R2 is setting all incoming routes from AS 1 with a weight of 100
> R3 is setting all incoming routes from AS1 with a weight of 200
>
> by default R4 sees routes in its BGP table from both R2 and R3
>
> Question
> when i set on R2 the weight of 200 to all incoming routes from R3.
> R4 no longer sees any routes in its BGP table from R2.
> is this because :-
>
> A R2 is no longer advetising them because the bgp routing process says not
> to advertise them to R4
>
> B R4 , the BGP proccess is seeing these routes from R2 with a lower weight
> and decides no tto use them.
>
> TIA
>
> stephen
> --
> Only two things are infinite, the universe and human stupidity, and I'm not
> sure about the former.
>
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