Cisco Catalyst 4500 Series Software Configuration Guide

24-8
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 24 Configuring Flex Links and MAC Address-Table Move Update
Configuring Flex Links
Configuring VLAN Load Balancing on Flex Links
To configure VLAN load balancing on Flex Links, perform this task:
To disable the VLAN load balancing feature, enter the no switchport backup interface prefer vlan
interface configuration command.
In this example, VLANs 1 to 50, 60, and 100 to 120 are configured on the switch:
Switch(config)# interface fastethernet 1/6
Switch(config-if)# switchport backup interface fastethernet 1/0/8 prefer vlan 60,100-120
When both interfaces are up, Fast Ethernet port 1/0/8 forwards traffic for VLANs 60 and 100 to 120 and
Fast Ethernet port 1/0/6 forwards traffic for VLANs 1 to 50.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
FastEthernet1/6 FastEthernet1/8 Active Up/Backup Standby
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
When a Flex Links interface shuts down, VLANs preferred on this interface are moved to the peer
interface of the Flex Links pair. In this example, if interface 1/6 shuts down, interface 1/8 carries all
VLANs of the Flex Links pair.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
FastEthernet1/6 FastEthernet1/8 Active Down/Backup VLB all
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
Command Purpose
Step 1
Switch# configure terminal
Enters global configuration mode.
Step 2
Switch(conf)# interface interface-id
Specifies the interface, and enters interface configuration
mode. The interface might be a physical Layer 2 interface
or a port channel (logical interface). The port channel
range is 1 to 48.
Step 3
Switch(conf-if)# switchport backup interface
interface-id prefer vlan vlan-range
Configures a physical Layer 2 interface (or port channel)
as part of a Flex Links pair with the interface, and
specifies the VLANs carried on the interface. The VLAN
ID range is 1 to 4094.
Step 4
Switch(conf-if)# end
Returns to privileged EXEC mode.
Step 5
Switch# show interfaces [interface-id] switchport
backup
Verifies the configuration.
Step 6
Switch# copy running-config startup config
(Optional) Saves your entries in the switch startup
configuration file.

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