8.4 Monitoring BGP Operation
8.4.1 Verifying BGP operation
Verify BGP operation by using the key show commands listed in Figure .

If the router has not installed the BGP routes expected, use the show ip bgp command to verify that BGP has learned these routes.

Note that the output of this command includes the BGP table version number, which increments each time the local router receives changed route information. The AS_Path, among other key attributes, is also included in this table. Routes that are deemed the best are denoted by the > character and are installed in the router's IP routing table.

If an expected BGP route does not appear in the BGP table, you can use the show ip bgp neighbors command to verify that your router has established a BGP connection with its neighbors.

The most important information output of this command is the BGP state that exists between the neighbors. Anything other than "Established" indicates that the peers are not fully communicating.

The show ip bgp neighbors command supports a number of optional parameters and uses the following syntax shown in Figure .