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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter21 Configuring EtherChannel Configuring EtherChannel
Configuring EtherChannel
This section describes these configurations for EtherChannel on Layer 2 and Layer 3 interf aces :
Default EtherChannel Configuration, page 21-7
EtherChannel Configuration Guidelines, page 21-8
Configuring Layer 2 EtherChannels, page 21-9
Configuring Layer 3 EtherChannels, page 21-11
Configuring EtherChannel Load Balancing, page 21-13
Configuring the PAgP Learn Method and Priority, page 21-14
Note Make sure that the interfaces are correctly confi gu red (s ee th e EtherC han nel Co nfigu rat ion
Guidelines section on page 21-8).
Note After you configure an EtherChannel, configuration changes applied to the port- chan nel inter face
apply to all the physical interfaces assigned to the port-ch annel interface, and configuration changes
applied to the physical interface affect only the interface where you apply the configuration.

Default EtherChannel Configuration

Table21-2 show s the defa ult E ther Cha nnel confi gura tio n.
Table21-2 Default EtherChannel Configuration
Feature Default Setting
Channel groups None assigned.
Layer 3 port-channel logical interface None defined.
PAgP mode Auto and silent (The interface is in a passive negotiating
state; it responds to PAgP packets it receives but does not
start PAgP packet negotiation. PAgP is enabled only if a
PAgP device is detected.)
PAgP learn method Aggregate-port learning on all interfaces.
PAgP priority 128 on all interfaces.
Load balancing Load distribution on the switch is based on the
source-MAC address of the incoming packet. Load
distribution based on the source and destination IP
address is also enabled for routed IP traffic.