Users Guide

Table Of Contents
2. Enable BFD globally in CONFIGURATION mode.
bfd enable
To verify that BFD is globally enabled, use the show running-config bfd command.
BFD global configuration
OS10(config)# bfd interval 250 min_rx 300 multiplier 4 role passive
OS10(config)# bfd enable
OS10(config)# do show running-config bfd
!
bfd enable
bfd interval 250 min_rx 300 multiplier 4 role passive
View information about active BFD neighbors
OS10#show bfd neighbors active
* - Active session role
-------------------------------------------------------------------------------------------
LocalAddr RemoteAddr Interface State RxInt TxInt Mult VRF Clients
-------------------------------------------------------------------------------------------
* 100.100.1.1 100.100.1.2 ethernet1/1/26:1 up 200 200 3 red ospfv2
* 100.100.3.1 100.100.3.2 ethernet1/1/26:3 up 200 200 3 default ospfv2
* 200.1.1.2 200.1.1.1 vlan102 up 200 200 3 black bgp
* 200.1.5.2 200.1.5.1 vlan105 up 200 200 3 default ospfv2
* 200.1.11.2 200.1.11.1 vlan111 up 200 200 3 green rtmv4
* 200.1.12.2 200.1.12.1 vlan112 up 200 200 3 default rtmv4
* 201.1.1.2 201.1.1.1 vlan101 up 200 200 3 green ospfv2
BFD for BGP
In a BGP core network, BFD enables faster network reconvergence. BFD rapidly detects communication failures in BGP fast-forwarding
paths between internal BGP (iBGP) and external BGP (eBGP) peers. BFD for BGP is supported on physical, port-channel, and VLAN
interfaces. BFD for BGP does not support the BGP multihop feature.
Before configuring BFD for BGP, first configure BGP on the interconnecting routers. For more information, see Border Gateway Protocol.
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.
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Layer 3