BGP NSR provides BGP nonstop routing (NSR) and nonstop forwarding (NSF) in the event of a switchover from an Active RP to
the Standby RP. The BGP NSR Support for iBGP Peers feature provides NSR support for iBGP peers configured under the IPv4 unicast
or IPv4 + label address family.
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and feature information,
Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module,
and to see a list of the releases in which each feature is supported, see the feature information table at the end of this
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature
Navigator, go to
www.cisco.com/go/cfn. An account on Cisco.com is not required.
Restrictions on BGP NSR Support for iBGP Peers
This feature applies to iBGP peers configured under IPv4 unicast or IPv4 +
label address families.
When you configure BGP with graceful restart and remove the BGP configuration
using no router bgp command, the graceful restart
timer starts. As a result, the stale entry is present in the BGP routing
table and it is only removed after the BGP graceful restart timer is
Information About BGP NSR Support for iBGP Peers
Benefit of BGP NSR Support for iBGP Peers
Nonstop routing is beneficial for iBGP peers because it reduces the likelihood of dropped packets during switchover from
the Active RP to the Standby RP. Switchover occurs when the Active RP fails for some reason, and the Standby RP takes control
of Active RP operations.
How to Configure BGP NSR Support for iBGP Peers
Making an iBGP Peer NSR-Capable for the IPv4 Address Family
Command or Action
Enables privileged EXEC mode.
Enter your password if prompted.
Device# configure terminal
Enters global configuration mode.
Device(config)# router bgp 4000
Enters router configuration mode for the specified routing process.
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