EtherChannel

What is it?

EtherChannel is a port link aggregation technology used primarily on Cisco switches. It allows grouping several physical Ethernet links to create one logical Ethernet link for the purpose of providing fault-tolerance and high-speed links between devices.

Port Modes

EtherChannel can be configured manually or you can use protocols for link aggregation. Protocols that can be used with EtherChannel are PAgP and LACP. The port states that results in aggregations are listed below for both protocols:

PAgP

PAgP Channel Mode	ON	AUTO	DESIRABLE
ON	Yes	No	No
AUTO	No	No	Yes
DESIRABLE	No	Yes	Yes

LACP

LACP Channel Mode	ON	PASSIVE	ACTIVE
ON	Yes	No	No
PASSIVE	No	No	Yes
ACTIVE	No	Yes	Yes