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Cisco − Troubleshooting BGP

Table of Contents
Troubleshooting BGP.........................................................................................................................................1
Document ID: 22166................................................................................................................................1
Interactive: This document offers customized analysis of your Cisco device........................................1
Introduction..........................................................................................................................................................1
Before You Begin................................................................................................................................................1
Conventions............................................................................................................................................1
Prerequisites............................................................................................................................................1
Components Used...................................................................................................................................1
Main Troubleshooting Flowchart........................................................................................................................2
Troubleshooting BGP Neighbor Establishment...................................................................................................2
Troubleshooting Routes Missing from the Routing Table..................................................................................3
Troubleshooting Multihoming Inbound...............................................................................................................4
Troubleshooting BGP Route Advertisement.......................................................................................................5
Troubleshooting Multihoming Outbound............................................................................................................6
Related Information.............................................................................................................................................7

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you must be a registered customer. If you have the output of a show ip bgp. If you are working in a live Cisco − Troubleshooting BGP . Prerequisites There are no specific prerequisites for this document. Before You Begin Conventions For more information on document conventions. you can use to display potential issues and fixes. see the Cisco Technical Tips Conventions. To use. or to go to the next flowchart.Troubleshooting BGP Document ID: 22166 Interactive: This document offers customized analysis of your Cisco device. click the command boxes in red. and have JavaScript enabled. All of the devices used in this document started with a cleared (default) configuration. and have JavaScript enabled. To see more information. be logged in. To use Output Interpreter. you must be a registered customer. You can use Output Interpreter to display potential issues and fixes. show ip bgp neighbor. The information presented in this document was created from devices in a specific lab environment. Components Used This document is not restricted to specific software and hardware versions. be logged in. or show tech−support command from your Cisco device. show ip bgp summary. Introduction Before You Begin Conventions Prerequisites Components Used Main Troubleshooting Flowchart Troubleshooting BGP Neighbor Establishment Troubleshooting Routes Missing from the Routing Table Troubleshooting Multihoming Inbound Troubleshooting BGP Route Advertisement Troubleshooting Multihoming Outbound Related Information Introduction This document provides troubleshooting information for common problems with Border Gateway Protocol (BGP).

Main Troubleshooting Flowchart Troubleshooting BGP Neighbor Establishment Cisco − Troubleshooting BGP .network. ensure that you understand the potential impact of any command before using it.

Troubleshooting Routes Missing from the Routing Table Cisco − Troubleshooting BGP .

Troubleshooting Multihoming Inbound Cisco − Troubleshooting BGP .

Troubleshooting BGP Route Advertisement Cisco − Troubleshooting BGP .

Troubleshooting Multihoming Outbound Cisco − Troubleshooting BGP .

Related Information • BGP Support Page • Technical Support − Cisco Systems All contents are Copyright © 1992−2005 Cisco Systems. 2006 Document ID: 22166 Cisco − Troubleshooting BGP . Inc. All rights reserved. Important Notices and Privacy Statement. Updated: Jan 10.