Pagp Learn-Method - Cisco Catalyst 3750 Command Reference Manual

Chapter 2 Catalyst 3750 Switch Cisco IOS Commands

pagp learn-method

Use the pagp learn-method interface configuration command on the switch stack or on a standalone
switch to learn the source address of incoming packets received from an EtherChannel port. Use the no
form of this command to return to the default setting.
Syntax Description
aggregation-port
physical-port
Defaults The default is aggregation-port (logical port channel).
Command Modes
Interface configuration
Command History Release
12.1(11)AX
Usage Guidelines
The learn method must be configured the same at both ends of the link.
The Catalyst 3750 switch supports address learning only on aggregate ports even though the
Note
physical-port keyword is provided in the command-line interface (CLI). The pagp learn-method and
the pagp port-priority interface configuration commands have no effect on the switch hardware, but
they are required for PAgP interoperability with devices that only support address learning by physical
ports, such as the Catalyst 1900 switch.
When the link partner to the Catalyst 3750 switch is a physical learner, we recommend that you configure
the switch as a physical-port learner by using the pagp learn-method physical-port interface
configuration command and to set the load-distribution method based on the source MAC address by
using the port-channel load-balance src-mac global configuration command. Use the pagp
learn-method interface configuration command only in this situation.
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pagp learn-method {aggregation-port | physical-port}
no pagp learn-method
Specify address learning on the logical port-channel. The switch sends
packets to the source using any of the ports in the EtherChannel. This setting
is the default. With aggregate-port learning, it is not important on which
physical port the packet arrives.
Specify address learning on the physical port within the EtherChannel. The
switch sends packets to the source using the same port in the EtherChannel
from which it learned the source address. The other end of the channel uses
the same port in the channel for a particular destination MAC or IP address.
Modification
This command was introduced.
Catalyst 3750 Switch Command Reference
pagp learn-method
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