set community question

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Richard Burts Fri, 06/15/2007 - 10:06
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Ben


The BGP community is a value that you assign to routes. It is essentially a tag that is associated with the route so that someone else can evaluate the tag and make some processing decision based on the tag value.


In general the number before the colon in the community value (like 7020) would be your AS number. The number after the colon (like 20) is some arbitrary value that you pick.


So what this generally means is that you have agreed with some BGP neighbor that if they see routes from you with community (tag) value of 7020:20 that they should take some particular action about those routes.


HTH


Rick

mohammedmahmoud Fri, 06/15/2007 - 10:29
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Hi Ben,


Just to add a tiny detail on the prefect explaination by Rick, to add the community to the already existing communities you must use the "additive" keyword, in your example if the matched (in the ACL 99) routes has already got any communities it will be replaced with the "7020:20".


HTH,

Mohammed Mahmoud.

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