Configuring BGP Conditional Route Injection

The BGP Conditional Route Injection feature is supported by all platforms in Cisco IOS Release 12.2(14)S that support BGP:

• Cisco 7200 series
• Cisco 7400 series
• Cisco 7500 series

Determining Platform Support Through Cisco Feature Navigator Cisco IOS software is packaged in feature sets that support specific platforms. To get updated information regarding platform support for this feature, access Cisco Feature Navigator. Cisco Feature Navigator dynamically updates the list of supported platforms as new platform support is added for the feature. Cisco Feature Navigator is a web-based tool that enables you to determine which Cisco IOS software images support a specific set of features and which features are supported in a specific Cisco IOS image.

You can search by feature or release. Under the release section, you can compare releases side by side to display both the features unique to each software release and the features in common.

See the following section for configuration tasks for the BGP Conditional Route Injection feature. Each task in the list is identified as either required or optional.

• Configuring BGP Conditional Route Injection (required)
• Verifying BGP Conditional Route Injection (optional)

To configure the BGP Conditional Route Injection feature, use the following commands beginning in global configuration mode:


CommandPurpose
Step 1Router(config)# router bgp as-numberPlaces the router in router configuration mode, and configures the router to run a BGP process.
Step 2Router(config-router)# bgp inject-map ORIGINATE
exist-map LEARNED_PATH		Configures the inject-map named ORIGINATE and the exist-map named LEARNED_PATH for conditional route injection.
Step 3Router(config-router)# exitExits router configuration mode, and enters global configuration mode.
Step 4Router(config)# route-map LEARNED_PATH permit
sequence-number		Configures the route map named
LEARNED_PATH.
Step 5Router(config-route-map)# match ip address prefix-list
ROUTE		Specifies the aggregate route to which a more specific route will be injected.
Step 6Router(config-route-map# match ip route-source
prefix-list ROUTE_SOURCE		Configures the prefix list named
ROUTE_SOURCE to redistribute the source of the route.

Note: The route source is the neighbor address that is configured with the neighbor remote-as command. The tracked prefix must come from this neighbor in order for conditional route injection to occur.
Step 7Router(config-route-map)# exitExits route-map configuration mode, and enters global configuration mode.
Step 8Router(config)# route-map ORIGINATE permit 10Configures the route map named ORIGINATE.
Step 9Router(config-route-map)# set ip address prefix-list ORIGINATED_ROUTESSpecifies the routes to be injected.
Step 10Router(config-route-map)# set community community-attribute additiveConfigures the community attribute of the injected routes.
Step 11Router(config-route-map)# exitExits route-map configuration mode, and enters global configuration mode.
Step 12Router(config)# ip prefix-list ROUTE permit
10.1.1.0/24		Configures the prefix list named ROUTE to permit routes from network 10.1.1.0/24.
Step 13Router(config)# ip prefix-list ORIGINATED_ROUTES
permit 10.1.1.0/25		Configures the prefix list named
ORIGINATED_ROUTES to permit routes from network 10.1.1.0/25.
Step 14Router(config)# ip prefix-list ORIGINATED_ROUTES
permit 10.1.1.128/25		Configures the prefix list named
ORIGINATED_ROUTES to permit routes from network 10.1.1.0/25.
Step 15Router(config)# ip prefix-list ROUTE_SOURCE permit
10.2.1.1/32		Configures the prefix list named
ROUTE_SOURCE to permit routes from network 10.2.1.1/32.

Note: The route source prefix list must be configured with a /32 mask in order for conditional route injection to occur.
Note: To enable conditional route injection, the exist-map must contain both the match ip address prefix-list and match ip route-source prefix-list match clauses in the route map paragraph.

Labels: