Cisco Cisco IOS Software Release 12.2(27)SBC
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BGP Support for Next-Hop Address Tracking
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.
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:
Cisco IOS BGP Configuration Guide, Release 12.4T, at the following URL:
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.
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