Cisco Catalyst 4500 Series Administration Guide

26-6
Software Configuration Guide—Release IOS XE 3.6.0E and IOS 15.2(2)E
OL_28731-01
Chapter 26 Configuring EtherChannel and Link State Tracking
Configuring EtherChannel
• For Layer 3 EtherChannels:
– Assign Layer 3 addresses to the port channel logical interface, not to the physical interfaces in
the channel.
• For Layer 2 EtherChannels:
– Assign all interfaces in the EtherChannel to the same VLAN, or configure them as trunks.
– If you configure an EtherChannel from trunk interfaces, verify that the trunking mode and the
native VLAN is the same on all the trunks. Interfaces in an EtherChannel with different trunk
modes or different native VLANs can have unexpected results.
– An EtherChannel supports the same allowed range of VLANs on all the interfaces in a trunking
Layer 2 EtherChannel. If the allowed ranges differ for selected interface differ, they do not form
an EtherChannel.
– Interfaces with different Spanning Tree Protocol (STP) port path costs can form an
EtherChannel as long they are otherwise compatibly configured. Setting different STP port path
costs does not make interfaces incompatible for the formation of an EtherChannel.
• After you configure an EtherChannel, any configuration that you apply to the port channel interface
affects the EtherChannel; any configuration that you apply to the physical interfaces affects only the
interface you configure.
Storm Control is an exception to this rule. For example, you cannot configure Storm Control on
some of the members of an EtherChannel; Storm Control must be configured on all or none of the
ports. If you configure Storm Control on only some of the ports, those ports are dropped from the
EtherChannel interface (put in suspended state). You should configure Storm Control at the port
channel interface level, and not at the physical interface level.
• A physical interface with port security enabled can join a Layer 2 EtherChannel only if port security
is also enabled on the EtherChannel; otherwise the command is rejected by the CLI.
• You cannot configure a 802.1X port in an EtherChannel.
Configuring EtherChannel
These sections describe how to configure EtherChannel:
• Configuring Layer 3 EtherChannels, page 26-7
• Configuring Layer 2 EtherChannels, page 26-10
• Configuring LACP Standalone or Independent Mode, page 26-12
• Configuring the LACP System Priority and System ID, page 26-13
• Configuring EtherChannel Load Balancing, page 26-14
• Removing an Interface from an EtherChannel, page 26-15
• Removing an EtherChannel, page 26-15
Note Ensure that the interfaces are configured correctly. See the “EtherChannel Configuration Guidelines and
Restrictions” section on page 26-5.

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