The BGP Conditional Route Injection feature is based on the injection of a more specific prefix into theBGP routing table when a less specific prefix is present. If conditional route injection is not workingproperly, check the following:
If conditional route injection is configured but does not occur, check for the existence of the aggregate prefix in the BGP routing table. The existence (or not) of the tracked prefix in the BGP
If the aggregate prefix exists but conditional route injection does not occur, verify that the aggregate prefix is being received from the correct neighbor and the prefix list identifying that neighbor is a /32 match.
Verify the injection (or not) of the more specific prefix using the show ip bgp injected-paths command.
Verify that the prefix that is being injected is not outside of the scope of the aggregate prefix.
Ensure that the inject route map is configured with the set ip address command and not the match ip address command.
Monitoring and Maintaining BGP Conditional Route Injection
To display BGP conditional advertisement information, use the following commands in EXEC mode, as needed:
Command: Router# show ip bgp
Purpose: Displays entries in the BGP routing table.
Command: Router# show ip bgp injected-paths
Purpose: Displays paths in the BGP routing table that were conditionally injected.
Command: Router# show ip bgp neighbors
Purpose: Displays information about the TCP and BGP connections to neighbors.
routing table can be verified with the show ip bgp command.
If the aggregate prefix exists but conditional route injection does not occur, verify that the aggregate prefix is being received from the correct neighbor and the prefix list identifying that neighbor is a /32 match.
Verify the injection (or not) of the more specific prefix using the show ip bgp injected-paths command.
Verify that the prefix that is being injected is not outside of the scope of the aggregate prefix.
Ensure that the inject route map is configured with the set ip address command and not the match ip address command.
Monitoring and Maintaining BGP Conditional Route Injection
To display BGP conditional advertisement information, use the following commands in EXEC mode, as needed:
Command: Router# show ip bgp
Purpose: Displays entries in the BGP routing table.
Command: Router# show ip bgp injected-paths
Purpose: Displays paths in the BGP routing table that were conditionally injected.
Command: Router# show ip bgp neighbors
Purpose: Displays information about the TCP and BGP connections to neighbors.
