bgp selection of routes

Unanswered Question
Oct 5th, 2007
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I'm receiving routes from my upstream providers..

How bgp selecting best route while I'm receiving routes with default parameters from both upstream providers

sh ip bgp

BGP routing table entry for, version 1658

Paths: (2 available, best #2, table Default-IP-Routing-Table)

Not advertised to any peer

38193 23966 from (

Origin IGP, localpref 100, valid, external

17557 23966 from (

Origin IGP, localpref 100, valid, external, best

You see second route is best while attributes are same...what else left which is deciding second route is best..

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jahilnt10 Fri, 10/05/2007 - 12:18
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thanks for sharing URL...I fall in #10..

old learned route is getting priorty over new one..

Collin Clark Fri, 10/05/2007 - 12:24
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Glad it helped.

HTH and please rate.

Mohamed Sobair Fri, 10/05/2007 - 14:44
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at your example, you can just use the AS-Prepending rule and apply it outpound direction to affect your incoming traffic if you want the second ISP to be prefered for specific Prefix.


Mohamed Sobair


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