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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-12247-04
Chapter 37 Configuring EtherChannels and Link-State Tracking
Understanding EtherChannels
Port-Channel Interfaces
When you create an EtherChannel, a port-channel logical interface is involved:
•
With Layer 2 ports, use the
channel-group
interface configuration command to dynamically create
the port-channel logical interface.
You also can use the
interface port-channel
port-channel-number
global configuration command
to manually create the port-channel logical interface, but then you must use the
channel-group
channel-group-number
command to bind the logical interface to a physical port. The
channel-group-number
can be the same as the
port
-
channel-number,
or you can use a new number.
If you use a new number, the
channel-group
command dynamically creates a new port channel.
•
With Layer 3 ports, you should manually create the logical interface by using the
interface
port-channel
global configuration command followed by the
no switchport
interface configuration
command. Then you manually assign an interface to the EtherChannel by using the
channel-group
interface configuration command.
For both Layer 2 and Layer 3 ports, the
channel-group
command binds the physical port and the logical
interface together as shown in
.
Each EtherChannel has a port-channel logical interface numbered from 1 to 64. This port-channel
interface number corresponds to the one specified with the
channel-group
interface configuration
command.
Figure 37-4
Relationship of Physical Ports, Logical Port Channels, and Channel Groups
After you configure an EtherChannel, configuration changes applied to the port-channel interface apply
to all the physical ports assigned to the port-channel interface. Configuration changes applied to the
physical port affect only the port where you apply the configuration. To change the parameters of all
ports in an EtherChannel, apply configuration commands to the port-channel interface, for example,
spanning-tree commands or commands to configure a Layer 2 EtherChannel as a trunk.
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Channel-group
binding
Physical ports
Logical
port-channel
