Cisco Systems 2960-S, 2960 Configuring the PAgP Learn Method and Priority

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Catalyst 2960 and 2960-S Switch Software Configuration Guide
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Chapter 37 Configuring EtherChannels and Link-State Tracking
Configuring EtherChannels
Beginning in privileged EXEC mode, follow these steps to configure EtherChannel load balancing. This
procedure is optional.
To return EtherChannel load balancing to the default configuration, use the no port-channel
load-balance global configuration command.
Configuring the PAgP Learn Method and Priority
Network devices are classified as PAgP physical learners or aggregate-port learners. A device is a
physical learner if it learns addresses by physical ports and directs transmissi ons based on that
knowledge. A device is an aggregate-port learner if it learns addresses by aggregate (logical) ports. The
learn method must be configured the same at both ends of the link.
When a device and its partner are both aggregate-port learners, they learn the address on the logical
port-channel. The device sends packets to the source by using any of the ports in the EtherChannel. With
aggregate-port learning, it is not important on which physical port the pack et arrives.
PAgP cannot automatically detect when the partner device is a physical learner and when the local device
is an aggregate-port learner. Therefore, you must manually set the learning method on the local device
to learn addresses by physical ports. You also must set the load-distribution method to source-based
distribution, so that any given source MAC address is always sent on the same physical port.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 port-channel load-balance {dst-ip | dst-mac |
src-dst-ip | src-dst-mac | src-ip | src-mac}
Configure an EtherChannel load-balancing method.
The default is src-mac.
Select one of these load-distribution methods:
• dst-ip—Load distribution is based on the destination-host IP
address.
• dst-mac—Load distribution is based on the destination-host
MAC address of the incoming packet.
• src-dst-ip—Load distribution is based on the
source-and-destination host-IP address.
• src-dst-mac—Load distribution is based on the
source-and-destination host-MAC address.
• src-ip—Load distribution is based on the source-host IP
address.
• src-mac—Load distribution is based on the source-MAC
address of the incoming packet.
Step 3 end Return to privileged EXEC mode.
Step 4 show etherchannel load-balance Verify your entries.
Step 5 copy running-config startup-config (Optional) Save your entries in the configuration file.