Cisco Cisco IOS Software Release 12.2(25)S
BGP Cost Community
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Cisco IOS Release 12.0(24)S, 12.0(27)S, 12.3(2)T, 12.2(18)S, 12.3(8)T, and 12.2(25)S
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Prerequisites for the BGP Cost Community Feature
This document assumes that BGP is configured in your network and that peering has been established.
Restrictions for the BGP Cost Community Feature
The following restrictions apply to the BGP Cost Community feature:
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The BGP Cost Community feature can be configured only within an autonomous system or
confederation. The cost community is a non-transitive extended community that is passed to iBGP
and confederation peers only and is not passed to eBGP peers.
confederation. The cost community is a non-transitive extended community that is passed to iBGP
and confederation peers only and is not passed to eBGP peers.
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The BGP Cost Community feature must be supported on all routers in the autonomous system or
confederation before cost community filtering is configured. The cost community should be applied
consistently throughout the local autonomous system or confederation to avoid potential routing
loops.
confederation before cost community filtering is configured. The cost community should be applied
consistently throughout the local autonomous system or confederation to avoid potential routing
loops.
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Multiple cost community set clauses may be configured with the set extcommunity cost command
in a single route map block or sequence. However, each set clause must be configured with a
different ID value (0-255) for each point of insertion (POI). The ID value determines preference
when all other attributes are equal. The lowest ID value is preferred.
in a single route map block or sequence. However, each set clause must be configured with a
different ID value (0-255) for each point of insertion (POI). The ID value determines preference
when all other attributes are equal. The lowest ID value is preferred.
Information About the BGP Cost Community Feature
To configure the BGP Cost Community feature, you must understand the following concepts:
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