40-8
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 40 Configuring Bidirection Forwarding Detection
How to Configure Bidirectional Forwarding Detection
The show bfd neighbor detail command displays print statistics for software and hardware (offloaded)
sessions. Hardware sessions provide a limited set of statistics. In particular, statistics for packet transmit
and receive intervals are not available for hardware sessions.
The holddown and hello counts are zero for all offloaded sessions.
Note Hardware offload is not supported for IPv6 BFD sessions.
How to Configure Bidirectional Forwarding Detection
You start a BFD process by configuring BFD on the interface. When the BFD process is started, no
entries are created in the adjacency database; in other words, no BFD control packets are sent or
received. BFD echo mode, which is supported in BFD Version 1, starting with Cisco IOS
Release 15.1(1)SG, is enabled by default.
BFD echo packets are sent and received, in addition to BFD control packets. The adjacency creation
takes places once you have configured BFD support for the applicable routing protocols. This section
contains the following procedures:
• Configuring BFD Session Parameters on the Interface, page 40-8 (required)
• Configuring BFD Support for Dynamic Routing Protocols, page 40-9 (required)
• Configuring BFD Support for Static Routing, page 40-13 (optional)
• Configuring BFD Echo Mode, page 40-15 (optional)
• Monitoring and Troubleshooting BFD, page 40-17 (optional)
Configuring BFD Session Parameters on the Interface
The steps in this procedure show how to configure BFD on the interface by setting the baseline BFD
session parameters on an interface. Repeat the steps in this procedure for each interface over which you
want to run BFD sessions to BFD neighbors.
To configure BFD session parameters, perform this task:
Command or Action Purpose
Step 1
enable
Switch> enable
Enables privileged EXEC mode.
• Enter your password if prompted.
Step 2
configure terminal
Switch# configure terminal
Enters global configuration mode.
Step 3
interface type number
Switch(config)# interface gigabitethernet 6/1
Enters interface configuration mode.