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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
OL-10101-02
Chapter 30 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 transmissions based on 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 learning only on aggregate ports 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 effect 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 physical learner that has the
channel-group interface configuration command set to on, set the load-distribution 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. Beginning in privileged
EXEC mode, follow these steps to configure the LACP port priority:
Step 4 show etherchannel load-balance Verify your entries.
Step 5 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Specify the interface for transmission, and enter interface configuration
mode.
Step 3 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.
Step 4 end Return to privileged EXEC mode.