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Cisco ME 3400 EthernetAccess Switch SoftwareConfiguration Guide
78-17058-01
Chapter31 Configuring EtherChannels Configuring EtherChannels
•For Layer 2 EtherChannels:
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Assign all ports in the EtherChannel to the same VLAN, or configure them as trunks. Ports with
different native VLANs cannot form an EtherChannel.
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If you configure an EtherChannel from trunk ports, verify that the trunking mode is t he same on
all the trunks. Inconsistent trunk modes on EtherChann el por ts c an have unexpec ted resul ts.
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An EtherChannel supports the same allowed range of VLANs on all the po rts i n a tru nking
Layer 2 EtherChannel. If the allowed range of VLANs is not the same, the port s do not form an
EtherChannel even when PAgP is set to the auto or desirable mode.
–
NNIs with different spanning-tree path costs can form an EtherChannel if they are otherwise
compatibly configured. Setting different spanning-tree path costs does not, by itself, make ports
incompatible for the formation of an EtherChannel.
•For Layer 3 EtherChannels, assign the Layer 3 address to the port-channel logical int erfac e, no t to
the physical ports in the channel.
Configuring Layer 2 EtherChannels
You configure Layer2 EtherChannels by assig ning port s to a channel grou p with the c hannel-group
interface configuration command. This command automatically creates the port-channel logical
interface.
Beginning in privileged EXEC mode, follow these steps to assign a Layer 2 Ethernet p ort to a L ayer 2
EtherChannel. This procedure is required.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify a physical port, and enter interface configuration mode.
Valid interfaces include physical ports.
For a PAgP EtherChannel, you can configure up to eight ports of
the same type and speed for the same group.
For a LACP EtherChannel, you can configure up to 16 Ethernet
ports of the same type. Up to eight ports can be active, and up to
eight ports can be in standby mode.
Note If the interface is a UNI, you must enter the port-type
nni interface configuration command before configuring
PAgP or L ACP.
Step3 switchport mode {access | trunk}
switchport access vlan vlan-id
Assign all ports as static-access ports in the same VLAN, or
configure them as trunks.
If you configure the port as a static-access port, assign it to only
one VLAN. The range is 1 to 4094.