BGP: Difference between revisions
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neighbor x.x.x.x send-community |
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 |
*BGP has default 4 well known communities that can be used to mark prefixes: |
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Internet: advertise these routes to all neighbors. |
Internet: advertise these routes to all neighbors. |
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Local-as: prevent sending routes outside the local As within the confederation. |
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. |
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. |
No-Export: do not advertise this route to external BGP peers. |
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*Communities can be used to mark a set of prefixes that share a common property. |
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*Upstream providers can use these marks to apply a common routing policy such as filtering or assigning a specific local preference. |
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*Set community attribute values by: |
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Network command |
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Aggregate address |
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Neighbor command |
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Redistribution |
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*Configuration |
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ip bgp-community new-format |
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route-map SETCOM |
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set community 1:10 |
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router bgp 12 |
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neighbor 192.168.12.2 remote-as 12 |
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neighbor 192.168.12.2 send-community |
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network 150.1.1.0 mask 255.255.255.0 route-map SETCOM ==> Network 150.1.1.0 is advertised with community 1:10 |
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= Route Aggregation = |
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= Synchronization = |
= Synchronization = |