BGP Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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BGP neighbor resets

Updated: February 28, 2026

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Overview

Explains administrative processes to refresh or clear BGP sessions using soft or hard resets to apply configuration changes and maintain routing accuracy.

BGP neighbor reset is an administrative process that

  • refreshes or clears BGP sessions to apply configuration changes

  • can be performed as a soft or hard reset, and

  • helps maintain accurate routing information by forcing policy re-evaluation or session re-establishment.

These resets are primarily categorized into two types, each with a distinct impact on the BGP session:

  • Soft reset: Resets only routing information without tearing down the TCP session.

  • Hard reset: Tears down the TCP session and removes all routes learned from the neighbor.

Reset BGP neighbors using inbound soft reset

Refresh inbound BGP policies and routes without resetting the entire session.

Context: Use this when inbound policy or attribute changes need to be applied to BGP-learned routes.

Before you begin

None

Procedure

1.

Run the show bgp neighbors command to verify the route refresh capability from the neighbor is enabled.

Example:

Router# show bgp neighbors
2.

Run the clear bgp command to initiate the inbound soft reset.

Example:

Router# clear bgp ipv4 unicast 10.0.0.1 soft in
  • Use * instead of specific IP address to reset all neighbors.
  • Use an AS number or external keyword for group resets.

The router requests the neighbor to resend routes, applying updated inbound policies.

Reset BGP neighbors using outbound soft reset

Resend all outbound BGP routes and policies to a neighbor.

Context: Use when outbound policy or attributes have changed.

Before you begin

None

Procedure

1.

Run the show bgp neighbors command to verify the route refresh capability from the neighbor is enabled.

Example:

Router# show bgp neighbors
2.

Run the clear bgp command to initiate the outbound soft reset.

Example:

Router# clear bgp ipv4 unicast 10.0.0.1 soft out
  • Use * instead of specific IP address to reset all neighbors.
  • Use an AS number or external keyword for group resets.

The router resends all routes for the specified address family to the neighbor.

Reset BGP neighbors using hard reset

Completely resets the TCP connection and clears all routing information from a BGP neighbor.

Context: Use if you need to force a full session re-establishment or resolve persistent connectivity issues.

A hard reset removes the TCP connection to the neighbor, removes all routes received from the neighbor from the BGP table, and then re-establishes the session with the neighbor. If the graceful keyword is specified, the routes from the neighbor are not removed from the BGP table immediately, but are marked as stale. After the session is re-established, any stale route that has not been received again from the neighbor is removed.

Before you begin

None

Procedure

Run the clear bgp command with optional graceful and soft keywords.

Example:

Router# clear bgp ipv4 unicast 10.0.0.3 graceful soft out
  • graceful : The graceful keyword preserves routes temporarily until the neighbor re-establishes.
  • Use * instead of specific IP address to reset all neighbors.
  • Use an AS number or external keyword for group resets.

The TCP session is terminated and re-established, and routing tables are refreshed.