User's Manual

40-20
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 40 Configuring EtherChannels and Link-State Tracking
Configuring EtherChannels
Beginning in privileged EXEC mode, follow these steps to configure your switch as a PAgP
physical-port learner and to adjust the priority so that the same port in the bundle is selected for sending
packets. This procedure is optional.
To return the priority to its default setting, use the no pagp port-priori
ty interface configuration
command. To return the learning method to its default setting, use the no pagp learn-method interface
configuration command.
Configuring LACP Hot-Standby Ports
When enabled, LACP tries to configure the maximum number of LACP-compatible ports in a channel,
up to a maximum of 16 ports. Only eight LACP links can be active at one time. The software places any
additional links in a hot-standby mode. If one of the active links becomes inactive, a link that is in the
hot-standby mode becomes active in its place.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface interface-id Specify the port for transmission, and enter interface
configuration mode.
Step 3
pagp learn-method physical-port Select the PAgP learning method.
By default, agg
regation-port learning is selected, which means
the switch sends packets to the source by using any of the ports
in the EtherChannel. With aggregate-port learning, it is not
important on which physical port the packet arrives.
Select ph
ysical-port to connect with another switch that is a
physical learner. Make sure to configure the port-channel
load-balance global configuration command to src-mac as
described in the “Configuring EtherChannel Load-Balancing”
section on page 40-18.
The learning method must be configured the same at both ends
of t
he link.
Step 4
pagp port-priority priority Assign a priority so that the selected port is chosen for packet
transmission.
For pri
ority, the range is 0 to 255. The default is 128. The higher
the priority, the more likely that the port will be used for PAgP
transmission.
Step 5
end Return to privileged EXEC mode.
Step 6
show running-config
or
show pagp c
hannel-group-number internal
Verify your entries.
Step 7
copy running-config startup-config (Optional) Save your entries in the configuration file.