Configuring BGP additional-paths and additional-path selection at address-family level

BGP additional-paths is configured by enabling the additional-paths capability and specifying paths that are candidates for selection as additional-paths.

About this task

BGP additional-paths is supported for the following BGP address families:
  • IPv4 unicast
  • IPv4 unicast VRF
  • IPv6 unicast
  • IPv6 unicast VRF

Perform the following task to enable the additional-paths capability and specify paths that are candidates for selection as additional-paths, under the IPv4 unicast address family.

Procedure

  1. From privileged EXEC mode, enter global configuration mode.
    device# configure terminal
    
  2. Enable BGP routing.
    device(config)# router bgp
    
  3. Enter configuration mode for the IPv4 unicast address family.
    device(config-bgp)# address-family ipv4 unicast
    
  4. Enable receiving and sending of additional paths.
    device(config-bgp-ipv4u)# additional-paths receive send
    
    A device can be configured to receive, send, or receive and send additional paths.
    Note

    Note

    A change to the additional-paths capability is activated only after restarting the BGP session.
  5. Specify paths that are candidates for selection as additional-paths. The following example specifies that all paths are candidates for selection as additional-paths.
    device(config-bgp-ipv4u)# additional-paths select all
    
    The all option configures all (up to a maximum of 16) paths as candidates for selection as additional-paths.

Example

The following example enables the receiving and sending of BGP additional-paths and specifies that all BGP paths are eligible for selection as additional-paths under the IPv4 unicast address family.

device# configure terminal
device(config)# router bgp
device(config-bgp)# address-family ipv4 unicast
device(config-bgp-ipv4u)# additional-paths receive send
device(config-bgp-ipv4u)# additional-paths select all

What to do next

After completing this task, restart the BGP session to activate the new additional-paths capability configuration.