Reference Guide

Bidirectional Forwarding Detection (BFD) | 163
To disable BFD sessions with all IS-IS neighbors out of an interface:
Configuring BFD for BGP
BFD for BGP is only supported on platforms: e c
In a BGP core network, BFD provides rapid detection of communication failures in BGP fast-forwarding
paths between internal BGP (iBGP) and external BGP (eBGP) peers for faster network reconvergence.
BFD for BGP is supported on 1GE, 10GE, 40GE, port-channel, and VLAN interfaces. BFD for BGP does
not support IPv6 and the BGP multihop feature.
Prerequisites
Before configuring BFD for BGP, you must first configure the following settings:
1. Configure BGP on the routers that you want to interconnect as described in Chapter 9, Border
Gateway Protocol IPv4 (BGPv4).
2. Enable fast fall-over for BGP neighbors to reduce convergence time (
neighbor fall-over command) as
described in BGP fast fall-over.
Establishing sessions with BGP neighbors
Before configuring BFD for BGP, you must first configure BGP on the routers that you want to
interconnect. For more information, refer to Chapter 9, Border Gateway Protocol IPv4 (BGPv4).
For example, the following illustration shows a sample BFD configuration on Router 1 and Router 2 that
use eBGP in a transit network to interconnect AS1 and AS2. The eBGP routers exchange information with
each other as well as with iBGP routers to maintain connectivity and accessibility within each autonomous
system.
Step Task Command Syntax Command Mode
1 Disable BFD sessions with all IS-IS
neighbors out of an interface.
isis bfd all-neighbors disable INTERFACE
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