Cisco Systems 2950 Default EtherChannel Configuration, EtherChannel Configuration Guidelines

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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
78-11380-10
Chapter31 Configuring EtherChannels
Configuring EtherChannels
Default EtherChannel Configuration
Table31-2 shows the de fault E t herCh ann el co nfigurati on .
EtherChannel Configuration Guidelines
If improperly configured, some EtherChannel interfaces are automatically disabled to avoid network
loops and other problems. Follow these guidelines to avoid configuration problems:
•Configure an EtherChannel with up to eight Ethernet interfaces of the same type.
Note Do not configure a GigaStack GBIC port as part of an EtherChannel.
•Configure all interfaces in an EtherChannel to o pera t e at th e s ame sp ee ds an d d upl ex m od es.
•Enable all interfaces in an EtherChannel. An interface 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 interfaces 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 secure port as part of an EtherChannel.
•Do not configure a port that is an active or a not-y et-a ctiv e me mber o f an Ether Channel as an 802 .1x
port. If you try to enable 802.1x on an EtherChannel port, an err or me ssa ge ap pe ars, a nd 802 .1x is
not enabled.
•If EtherChannels are configured on switch interfaces, remove the EtherChannel con figuration from
the interfaces before globally enabling 802.1x on a switch by using the dot1x system-auth-control
global configuration command.
Table31-2 Default EtherChannel Configuration
Feature Default Setting
Channel groups None assigned.
PAgP mode No default.
PAgP learn method Aggregate-port learning on all interfaces.
PAgP priority 128 on all interfaces. (Changing this value has no effect.)
LACP learn method Aggregate-port learning on all interfaces.
LACP priority 32768 on all interfaces.
Load balancing Load distribution on the switch is based on the
source-MAC address of the incoming packet.