BGP Support for Next-Hop Address Tracking

Table Of Contents

BGP Support for Next-Hop Address Tracking

Configuration Information

Command Reference Information

Master Commands Lists

BGP Support for Next-Hop Address Tracking

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The BGP Support for Next-Hop Address Tracking feature is enabled by default when a supporting Cisco IOS software image is installed. Border Gateway Protocol (BGP) next-hop address tracking is event driven. BGP prefixes are automatically tracked as peering sessions are established. Next-hop changes are rapidly reported to the BGP routing process as they are updated in the Routing Information Base (RIB). This optimization improves overall BGP convergence by reducing the response time to next-hop changes for routes installed in the RIB. When a best-path calculation is run in between BGP scanner cycles, only next-hop changes are tracked and processed.

Configuration Information

Configuration information is included in the "Configuring Advanced BGP Features" module of the Cisco IOS BGP Configuration Guide, Release 12.4T, at the following URL:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios124/124tcg/tbgp_c/brbadv.htm

The following sections provide information about this feature:

•BGP Support for Next-Hop Address Tracking

•Configuring BGP Next-Hop Address Tracking

•Enabling and Disabling BGP Next-Hop Address Tracking: Example

•Adjusting the Delay Interval for BGP Next-Hop Address Tracking: Example

For a complete list of features included in the "Configuring Advanced BGP Features" module, see the Feature Information table located toward the end of the module.

Command Reference Information

The following command is new or modified for this feature:

•bgp nexthop

Detailed information about this command is included in the Cisco IOS IP Routing: BGP Command Reference at the following URL:

http://www.cisco.com/en/US/docs/ios/iproute_bgp/command/reference/irg_book.html

Master Commands Lists

Cisco IOS master commands lists provide an alphabetical list of all Cisco IOS commands in a Cisco IOS release.

Cisco IOS new, modified, removed, and replaced commands lists provide an alphabetized list of all new, modified, removed, and replaced commands in a Cisco IOS release.

Release 12.2SB

Cisco IOS Master Commands List, Release 12.2SB, at the following URL:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122sb/122sbrln/122sbix.htm

Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.

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