Cisco Catalyst 4500 Series Software Configuration Guide

40-2
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
Contents
Contents
• Prerequisites for Bidirectional Forwarding Detection, page 40-2
• Restrictions for Bidirectional Forwarding Detection, page 40-2
• Information About Bidirectional Forwarding Detection, page 40-3
• How to Configure Bidirectional Forwarding Detection, page 40-8
• Configuration Examples for Bidirectional Forwarding Detection, page 40-17
• Additional References, page 40-28
Prerequisites for Bidirectional Forwarding Detection
Prerequisites include:
• IP routing must be enabled on all participating switches.
• One of the IP routing protocols supported by BFD must be configured on the switches before BFD
is deployed. You should implement fast convergence for the routing protocol that you plan to use.
See the IP routing documentation for your version of Cisco IOS software for information on
configuring fast convergence. See the “Restrictions for Bidirectional Forwarding Detection” section
on page 40-2 for more information on BFD routing protocol support in Cisco IOS software.
Restrictions for Bidirectional Forwarding Detection
Restrictions include:
• BFD works only for directly connected neighbors. BFD neighbors must be no more than one IP hop
away. Multihop configurations are not supported.
Cisco IOS Release 15.1(1)SG
• Catalyst 4500 Series Switches support up to 128 BFD sessions with a minimum hello interval of 100
ms and a multiplier of 3. The multiplier specifies the minimum number of consecutive packets that
can be missed before a session is declared down.
• If SSO is enabled on a dual RP system, the following limitations apply:
– The minimum hello interval is 100 ms with a multiplier of 5 or higher.
– Smaller values may be configured but may flap during an SSO switchover.
• To enable echo mode the peer system must be configured with the no ip redirects command.
Cisco IOS Release XE 3.5.0E and IOS 15.2(1)E
• Catalyst 4500 Series Switches support up to 100 BFD sessions with a minimum hello interval of 100
ms and a multiplier of 3. The multiplier specifies the minimum number of consecutive packets that
can be missed before a session is declared down.
• If SSO is enabled on a dual RP system, the following limitations apply:
– The minimum hello interval is 100 ms with a multiplier of 5 or higher.
– Smaller values may be configured but may flap during an SSO switchover.
• To enable echo mode the peer system must be configured with the no ip redirects command.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E