BGP: Difference between revisions
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= Community = |
= Community = |
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Source: [http://www.networkers-online.com/blog/2008/09/understanding-bgp-communities/ networkers-online.com] |
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{{UC}} |
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*A numerical value that can be assigned to a specific prefix and advertised to other neighbors. |
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*When the neighbor receives the prefix it will examine the community value and take proper action whether it is filtering or modifying other attributes. |
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*By default the community attribute is removed from the update before being sent to the neighbor. |
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*To allow community values to be sent to a specific neighbor |
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neighbor x.x.x.x send-community |
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*BGP has default 4 well known communities that can be used to mark prefixes; listed as follows: |
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Internet: advertise these routes to all neighbors. |
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Local-as: prevent sending routes outside the local As within the confederation. |
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No-Advertise: do not advertise this route to any peer, internal or external. |
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No-Export: do not advertise this route to external BGP peers. |
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= Synchronization = |
= Synchronization = |