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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter37 Configuring EtherChannels and Link-State Tracking
Understanding EtherChannels
Port-Channel Interfaces
When you create an EtherChannel, a port-channel lo gica l in terfa ce i s involved:
With Layer 2 ports, use the channel-group interface configurati on command to dyna mically 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 inte rface by usi ng t h e int erf ac e
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 por t and the logical
interface together as shown in Figure37-4.
Each EtherChannel has a port-channel logical interface numbered from 1 to 48. This port-c hannel
interface number corresponds to the one specified with the channel-group interface configuration
command.
Figure37-4 Relationship of Physical Ports, Logical Port Channels, and Channel Groups
After you configure an EtherChannel, configurati on chan ges appli ed to th e port -ch anne l inter fa ce ap ply
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 po rt-c ha nnel in terfa ce , fo r examp le,
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