BGP Peers States and Configuration
Question
-- Exhibit --
user@router> show bgp summary
Groups: 2 Peers: 2 Down peers: 2
Table Tot Paths Act Paths Suppressed History Damp State Pending inet.0
0 0 0 0 0 0
Peer AS InPkt OutPkt OutQ Flaps Last Up/Dwn State...
5.1.1.1 100 1 0 0 14:06 OpenConfirm
10.1.1.1 200 0 1 14:06 Active
-- Exhibit --
Click the Exhibit button.
Two newly configured BGP peers have remained in the states shown in the exhibit for several hours.
Which two statements are true? (Choose two.)
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.BD
From the output of the "show bgp summary" command, we can see that there are two BGP peers configured and both of them are currently in an incomplete state. Specifically:
Peer 5.1.1.1 (AS 100) is in the OpenConfirm state. This means that the BGP peering process has reached the point where the local router has sent an OPEN message to this peer, but the local router has not yet received a KEEPALIVE message from the peer in response. The TCP three-way handshake has completed successfully with this peer.
Peer 10.1.1.1 (AS 200) is in the Active state. This means that the BGP peering process has not yet reached the point where the local router has sent an OPEN message to this peer. Instead, the local router is still attempting to establish a TCP connection with this peer. The TCP three-way handshake has not completed successfully with this peer.
Given this information, we can determine which of the answer choices are true:
A. The TCP three-way handshake has completed successfully with the 10.1.1.1 peer. - False. As explained above, the local router has not yet completed the TCP three-way handshake with this peer.
B. The TCP three-way handshake has completed successfully with the 5.1.1.1 peer. - True. As explained above, the local router has successfully completed the TCP three-way handshake with this peer.
C. The local router has received a BGP keepalive message from the 5.1.1.1 peer. - False. The 5.1.1.1 peer is still in the OpenConfirm state, which means that the local router has not yet received a KEEPALIVE message from this peer.
D. The local router is initiating a transport protocol connection with the 10.1.1.1 peer. - True. As explained above, the local router is still attempting to establish a TCP connection with this peer.
