Users Guide

Table Of Contents
BFD for BGP example
In this BFD for BGP configuration example, Router 1 and Router 2 use eBGP in a transit network to interconnect AS1 and AS2.
The eBGP routers exchange information with each other and with iBGP routers to maintain connectivity and accessibility within
each autonomous system.
When you configure a BFD session with a BGP neighbor, you can:
Establish a BFD session with a specified BGP neighbor using the neighbor ip-address and bfd commands.
Establish BFD sessions with all neighbors discovered by BGP using the bfd all-neighbors command.
For example:
Router 1
OS10(conf)# bfd enable
OS10(conf)# router bgp 1
OS10(config-router-bgp-1)# neighbor 2.2.4.3
OS10(config-router-neighbor)# bfd
OS10(config-router-neighbor)# no shutdown
OR
OS10(conf)# bfd enable
OS10(conf)# router bgp 1
OS10(config-router-bgp-1)# bfd all-neighbors interval 200 min_rx 200 multiplier 6 role
active
Router 2
OS10(conf)# bfd enable
OS10(conf)# router bgp 2
OS10(config-router-bgp-2)# neighbor 2.2.4.2
OS10(config-router-neighbor)# bfd
OS10(config-router-neighbor)# no shutdown
OR
OS10(conf)# bfd enable
OS10(conf)# router bgp 2
OS10(conf-router-bgp-2)# bfd all-neighbors interval 200 min_rx 200 multiplier 6 role
active
BFD packets originating from a router are assigned to the highest priority egress queue to minimize transmission delays.
Incoming BFD control packets received from the BGP neighbor are assigned to the highest priority queue within the control
plane policing (CoPP) framework to avoid BFD packets drops due to queue congestion.
BFD notifies BGP of any failure conditions that it detects on the link. BGP initiates recovery actions.
BFD for BGP is supported only on directly connected BGP neighbors and in both BGP IPv4 and IPV6 networks. A maximum of
100 simultaneous BFD sessions are supported.
If each BFD for BGP neighbor receives a BFD control packet within the configured BFD interval for failure detection, the BFD
session remains up and BGP maintains its adjacencies. If a BFD for BGP neighbor does not receive a control packet within
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Layer 3