Etherchannel Overview; C H A P T E R 27 Configuring Etherchannels - Cisco Catalyst 3750 Software Configuration Manual

Understanding EtherChannels

EtherChannel Overview

An EtherChannel consists of individual Fast Ethernet or Gigabit Ethernet links bundled into a single
logical link as shown in
Figure 27-1 Typical EtherChannel Configuration
The EtherChannel provides full-duplex bandwidth up to 800 Mbps (Fast EtherChannel) or 2 Gbps
(Gigabit EtherChannel) between your switch and another switch or host. You cannot bundle standard
Gigabit Ethernet ports with the enhanced-services (ES) Gigabit Ethernet ports.
Each EtherChannel can consist of up to eight compatibly configured Ethernet ports. All ports in each
EtherChannel must be configured as either Layer 2 or Layer 3 ports. For Catalyst 3750 Metro switches,
the number of EtherChannels is limited to 12. For more information, see the
Configuration Guidelines" section on page
ports. Routed ports are physical ports configured to be in Layer 3 mode by using the no switchport
interface configuration command. For more information, see the
Characteristics."
If a link within an EtherChannel fails, traffic previously carried over that failed link changes to the
remaining links within the EtherChannel. A trap is sent for a failure, identifying the switch, the
EtherChannel, and the failed link. Inbound broadcast and multicast packets on one link in an
EtherChannel are blocked from returning on any other link of the EtherChannel.
Catalyst 3750 Metro Switch Software Configuration Guide
27-2
Figure 27-1.
Catalyst 8500
series switch
Gigabit EtherChannel
1000BASE-X
10/100
Switched
links
Workstations
1000BASE-X
10/100
Switched
links
Workstations
27-9. The EtherChannel Layer 3 ports are made up of routed
Chapter 27 Configuring EtherChannels
"EtherChannel
Chapter 9, "Configuring Interface
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