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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Chapter31 Configuring EtherChannels
Configuring EtherChannels
To return EtherChannel load balancing to the default configuration, use the no port-channel
load-balance global configuration command.
Configuring the PAgP Learn Method and Priority
Network devices are classified as PAgP physical learners or aggregate-port learners. A device is a
physical learner if it learns addresses by physical ports and directs transmissi ons ba sed o n that
knowledge. A device is an aggregate-port learner if it learns addresses by aggregate ports.
For compatibility with Catalyst 1900 series switches, configure the Catalyst 2950 and Catalyst 2955
switch for source-MAC load distribution.
The Catalyst 2950 or Catalyst 2955 switch supports address lear ning on ly on a gg regate por ts even
though the physical-port keyword is provided in the command-line interface (CLI). The pagp
learn-method and the pagp port-priority interface configuration command have no effe ct on the switch
hardware.
Note You should not set the learn method to physical-port because the switch is an aggregate-learning device.
If the link partner to the switch is a physical learner that has the channel-group interface configuration
command set to auto or desirable, the switch automatically uses the load-distribution method based on
the source MAC address, regardless of the configured load distribution method.
If the link partner to the Catalyst 2950 or Catalyst 2955 switch is a physic al learn er t hat has the
channel-group interface configuration command set to on, set the load-distr ibution method based on the
source MAC address by using the port-channel load-balance src-mac global configuration command.
Configuring the LACP Port Priority
You can set the priority for each port in an EtherChannel that is configured for LACP by using the
lacp port-priority privileged EXEC command. The range is from 1 to 65535. Beginni ng in privileged
EXEC mode, follow these steps to configure the LACP port priority:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the interface for transmission, and enter interface configuration
mode.
Step3 lacp port-priority priority-value Select the LACP port priority value.
For priority-value, the range is 1 to 65535. By default, the priority value is
32768. The lower the range, the more likely that the interface will be used
for LACP transmission.
Step4 end Return to privileged EXEC mode.
Step5 show running-config
or
show lacp channel-group-number
internal
Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.