Hello Guys,

Continuing the initiative of the blog to be reference in the study of Cisco Certifications, now present a summary of messages and states of the BGP protocol.

Below.

BGP messages:

• Open: When the BGP process starts are established connections to TCP port 179 to the BGP OPEN message.

• KeepAlive: KeepAlive indicating that the connection is still established.

• Update: update network messages. Sent early in the process and when updates occur on the network.

• Notification: When a neighbor restart Notification is sent a message indicating that the relationship is ending.

BGP states:

• Idle - Seeking neighbors.

• Connect - TCP connection established with neighbor

• Open Sent - BGP OPEN message sent

• Open Confirm - Response received

• Established - BGP neighbor Connection established.

Troubleshooting

• Established is good, rest is the problem.
• If the neighboring state of not progressing to Idle, verify that the next-hop is achievable.
• If the neighbor is in state Active is not configured or is not behaving as expected.
• Make sure the neighbor is correct: IP addresses, Autonomous System (AS), configuration and authentication.

A hug staff,

Maurício.

This entry was posted on Saturday, April 18th, 2009 at %I:%M %p and is filed under BGP, BSCI, CCNP, Resumos. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.