Configuring Layer 2 Etherchannels - Cisco Catalyst 2360 Software Configuration Manual

Chapter 26 Configuring EtherChannels and Link-State Tracking
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Configuring Layer 2 EtherChannels

You configure Layer 2 EtherChannels by assigning ports to a channel group with the channel-group
interface configuration command.
Beginning in privileged EXEC mode, follow these steps to assign a Layer 2 Ethernet port to a Layer 2
EtherChannel. This procedure is required.
Command
Step 1 configure terminal
Step 2
interface interface-id
OL-19808-01
When a group is first created, all ports follow the parameters set for the first port to be added to the
group. If you change the configuration of one of these parameters, you must also make the changes
to all ports in the group:
– Allowed-VLAN list
– Spanning-tree path cost for each VLAN
– Spanning-tree port priority for each VLAN
– Spanning-tree Port Fast setting
Do not configure a port to be a member of more than one EtherChannel group.
Do not configure an EtherChannel in both the PAgP and LACP modes. EtherChannel groups
running PAgP and LACP can coexist on the same switch. Individual EtherChannel groups can run
either PAgP or LACP, but they cannot interoperate.
Do not configure a Switched Port Analyzer (SPAN) destination port as part of an EtherChannel.
Do not configure a secure port as part of an EtherChannel or the reverse.
For Layer 2 EtherChannels:
Assign all ports in the EtherChannel to the same VLAN, or configure them as trunks. Ports with
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different native VLANs cannot form an EtherChannel.
If you configure an EtherChannel from trunk ports, verify that the trunking mode
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(IEEE 802.1Q) is the same on all the trunks. Inconsistent trunk modes on EtherChannel ports
can have unexpected results.
– An EtherChannel supports the same allowed range of VLANs on all the ports in a trunking
Layer 2 EtherChannel. If the allowed range of VLANs is not the same, the ports do not form an
EtherChannel even when PAgP is set to the auto or desirable mode.
Ports with different spanning-tree path costs can form an EtherChannel if they are otherwise
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compatibly configured. Setting different spanning-tree path costs does not, by itself, make ports
incompatible for the formation of an EtherChannel.
Purpose
Enter global configuration mode.
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.
Catalyst 2360 Switch Software Configuration Guide
Configuring EtherChannels
26-11