Configuring EtherChannel Load Balancing - dummies

Configuring EtherChannel Load Balancing

By Edward Tetz

EtherChannel can use two methods for load balancing Cisco device connections, with the default load balancing based on the source MAC address of the system sending data. But because it is sometimes more important for some data to be received rather than sent, Cisco gives you a choice.

The two methods you can use for load balancing are Source MAC (src-mac) and Destination MAC (dst-mac). So, what exactly does all this mean? When load balancing the connection, the switch takes a look at the MAC addresses in the packet header to determine which link is used for the data.

In the src-mac mode (the default load balancing mode), the switch looks at the frame source MAC address, then it passes all frames it sees from the same source MAC address through one of the links. dst-mac works the same way, but it classifies the frames based on the destination and will always pass data from that MAC address through the same link.

To configure load balancing, use the following commands:

Switch1> enable
Switch1# configure terminal 
Switch1(config)# port-channel load-balance dst-mac
Switch1(config)# end 

To view this setting, use the show command, as shown here:

Switch1> enable
Switch1# show etherchannel load-balance
Destination MAC address