Chapter 28
Configuring EtherChannels
Default EtherChannel Configuration
Table 28-3
Table 28-3
Feature
Channel groups
Port-channel logical interface
PAgP mode
PAgP learn method
PAgP priority
LACP mode
LACP learn method
LACP port priority
LACP system priority
LACP system ID
Load balancing
EtherChannel Configuration Guidelines
If improperly configured, some EtherChannel ports are automatically disabled to avoid network loops
and other problems. Follow these guidelines to avoid configuration problems:
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•
•
•
•
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OL-23400-01
shows the default EtherChannel configuration.
Default EtherChannel Configuration
Do not try to configure more than 26 EtherChannels on the switch.
Configure all ports in an EtherChannel to operate at the same speeds and duplex modes.
Enable all ports in an EtherChannel. A port in an EtherChannel that is disabled by using the
shutdown interface configuration command is treated as a link failure, and its traffic is transferred
to one of the remaining ports in the EtherChannel. ME 3800X and ME 3600X ports are enabled by
default.
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.
Default Setting
None assigned.
None defined.
No default.
Aggregate-port learning.
128.
No default.
Aggregate-port learning.
32768.
32768.
LACP system priority and the switch MAC address.
Load distribution on the switch is based on the
source-MAC address of the incoming packet.
Cisco ME 3800X and 3600X Switch Software Configuration Guide
Configuring EtherChannels
28-9