Advanced Configuration and Management Guide

 

Table 10.4: BGP4 Summary Information (Continued)

 

 

 

This Field...

 

Displays...

 

 

 

State

 

The state of this router’s neighbor session with each neighbor. The

 

 

states are from this router’s perspective of the session, not the

 

 

neighbor’s perspective. The state values are based on the BGP4

 

 

state machine values described in RFC 1771 and can be one of the

 

 

following for each router:

 

 

• IDLE – The BGP4 process is waiting to be started. Usually,

 

 

enabling BGP4 or establishing a neighbor session starts the

 

 

BGP4 process.

 

 

• A minus sign (-) indicates that the session has gone down

 

 

and the software is clearing or removing routes.

 

 

• ADMND – The neighbor has been administratively shut down.

 

 

See “Administratively Shutting Down a Session with a BGP4

 

 

Neighbor” on page 10-22.

 

 

• A minus sign (-) indicates that the session has gone down

 

 

and the software is clearing or removing routes.

 

 

• CONNECT – BGP4 is waiting for the connection process for the

 

 

TCP neighbor session to be completed.

 

 

• ACTIVE – BGP4 is waiting for a TCP connection from the

 

 

neighbor.

 

 

Note: If the state frequently changes between CONNECT and

 

 

ACTIVE, there may be a problem with the TCP connection.

 

 

• OPEN SENT – BGP4 is waiting for an Open message from the

 

 

neighbor.

 

 

• OPEN CONFIRM – BGP4 has received an OPEN message from

 

 

the neighbor and is now waiting for either a KEEPALIVE or

 

 

NOTIFICATION message. If the router receives a KEEPALIVE

 

 

message from the neighbor, the state changes to Established. If

 

 

the message is a NOTIFICATION, the state changes to Idle.

 

 

• ESTABLISHED – BGP4 is ready to exchange UPDATE packets

 

 

with the neighbor.

 

 

• If there is more BGP data in the TCP receiver queue, a plus

 

 

sign (+) is also displayed.

 

 

Note: If you display information for the neighbor using the

 

 

show ip bgp neighbor <ip-addr> command, the TCP

 

 

receiver queue value will be greater than 0.

 

 

 

Time

 

The time that has passed since the state last changed.

 

 

 

RtRecv

 

The total number or routes received in UPDATE messages from the

 

 

neighbor since the session was first established.

 

 

 

RtAcpt

 

The number of routes received from the neighbor that this router

 

 

actually installed in the BGP4 route table. Usually, this number is

 

 

lower than the RoutesRcvd number. The difference indicates that this

 

 

router filtered out some of the routes received in the UPDATE

 

 

messages.

 

 

 

10 - 86