Chapter 27
Configuring EtherChannels
Default EtherChannel Configuration
Table 27-3
Table 27-3 Default EtherChannel Configuration
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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78-15870-01
shows the default EtherChannel configuration.
More than 12 EtherChannels cannot be configured on the switch.
Do not bundle standard Gigabit Ethernet ports with the enhanced-services (ES) Gigabit Ethernet
ports.
Configure a PAgP EtherChannel with up to eight Ethernet ports of the same type.
Configure a LACP EtherChannel with 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.
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.
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.
Default Setting
None assigned.
None defined.
No default.
Aggregate-port learning on all ports.
128 on all ports.
No default.
Aggregate-port learning on all ports.
32768 on all ports.
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.
Catalyst 3750 Metro Switch Software Configuration Guide
Configuring EtherChannels
27-9