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Catalyst 2975 Switch Software Configuration Guide
OL-19720-02
Chapter 37 Configuring EtherChannels and Link-State Tracking
Configuring EtherChannels
You also can configure a single port within the group for all transmissions and use other ports for hot
standby. The unused ports in the group can be swapped into operation in just a few seconds if the selected
single port loses hardware-signal detection. You can configure which port is always selected for packet
transmission by changing its priority with the
pagp port-priority
interface configuration command. The
higher the priority, the more likely that the port will be selected.
Note
The switch supports address learning only on aggregate ports even though the
physical-port
keyword
is provided in the CLI. The
pagp learn-method
command and the
pagp port-priority
command have
no effect on the switch hardware, but they are required for PAgP interoperability with devices that only
support address learning by physical ports.
When the link partner of the switch is a physical learner (such as a Catalyst 1900 series switch), we
recommend that you configure the Catalyst 2975 switch as a physical-port learner by using the
pagp
learn-method physical-port
interface configuration command. Set the load-distribution method based
on the source MAC address by using the
port-channel load-balance src-mac
global configuration
command. The switch then sends packets to the Catalyst 1900 switch using the same port in the
EtherChannel from which it learned the source address. Only use the
pagp learn-method
command in
this situation.
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.
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,
aggregation-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
physical-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”
.
The learning method must be configured the same at both ends
of the link.
Step 4
pagp port-priority
priority
Assign a priority so that the selected port is chosen for packet
transmission.
For
priority
, 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.
Содержание 2975 - Catalyst LAN Base Switch
Страница 36: ...Contents xxxvi Catalyst 2975 Switch Software Configuration Guide OL 19720 02 ...
Страница 40: ...xxxviii Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Preface ...
Страница 62: ...1 22 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 1 Overview Where to Go Next ...
Страница 398: ...13 30 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 13 Configuring VLANs Configuring VMPS ...
Страница 424: ...15 18 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 15 Configuring VTP Monitoring VTP ...
Страница 628: ...26 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 26 Configuring UDLD Displaying UDLD Status ...
Страница 660: ...28 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 28 Configuring RMON Displaying RMON Status ...
Страница 888: ...38 32 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 38 Troubleshooting Troubleshooting Tables ...