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Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
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Chapter 6 Configuring Fast EtherChannel and Gigabit EtherChannel
Configuring EtherChannel Using PAgP
Creating an EtherChannel
You create an EtherChannel port bundle by specifying the ports in the channel and the channeling mode.
When you create an EtherChannel, an administrative group number is assigned automatically if one is
not already assigned to the specified ports. In addition, a channel ID is assigned.
The silent and non-silent keywords function only with the auto and desirable modes.
To create an EtherChannel port bundle, perform this task in privileged mode:
This example shows how to create an EtherChannel bundle and verify the configuration:
Console> (enable) set port channel 3/5-6 on
Port(s) 3/5-6 are assigned to admin group 57.
Port(s) 3/5-6 channel mode set to on.
Console> (enable) show port channel
Port Status Channel Admin Ch
Mode Group Id
----- ---------- -------------------- ----- -----
3/5 connected on 57
835
3/6 connected on 57
835
----- ---------- -------------------- ----- -----
Port Device-ID Port-ID Platform
----- ------------------------------- ------------------------- ----------------
3/5 069003103(5500) 3/5 WS-C4000
3/6 069003103(5500) 3/6 WS-C4000
----- ------------------------------- ------------------------- ----------------
Console> (enable)
Defining an EtherChannel Administrative Group
You can define EtherChannel administrative groups manually to identify groups of ports that are allowed
to form an EtherChannel bundle. When you create an EtherChannel port bundle, an administrative group
is defined automatically. Administrative group membership is limited by hardware restrictions.
The admin_group can be any value between 1 and 1024, inclusive.
Caution
Modifying the EtherChannel administrative group on connected ports causes the specified ports to be
removed from and then added to spanning tree (a spanning tree topology change occurs and the ports
must enter listening and learning mode before returning to forwarding mode).
Task
Command
Step 1
If you are unsure which ports you can configure as
an EtherChannel, verify the EtherChannel
capabilities for the module or switch that you are
configuring.
show port capabilities [mod_num[/port_num]]
Step 2
Create an EtherChannel with the desired ports.
set port channel port_list [admin_group] mode
{on | off | desirable | auto} [silent | non-silent]
Step 3
Verify the EtherChannel configuration.
show port channel [port_list]