Aggregation group, member port, and aggregate interface

Link bundling is implemented through interface bundling. An aggregation group is a group of Ethernet interfaces bundled together, which are called member ports of the aggregation group. For each aggregation group, a logical interface (called an aggregate interface), is created. When an upper layer entity uses the link aggregation service, the following events occur:

• A link aggregation group appears the same as a single logical link.

• An aggregate interface transmits data traffic.

When you create an aggregate interface, the device automatically creates an aggregation group of the same type and number as the aggregate interface. For example, when you create aggregate interface 1, aggregation group 1 is created.

Aggregate interfaces include Layer 2 aggregate interfaces and Layer 3 aggregate interfaces.

You can assign Layer 2 Ethernet interfaces only to a Layer 2 aggregation group, and Layer 3 Ethernet interfaces only to a Layer 3 aggregation group.

	NOTE: You can use the port link-mode command to configure an Ethernet port as a Layer 2 or Layer 3 interface (see "Configuring Ethernet interfaces").

On a Layer 3 aggregate interface, you can create subinterfaces.

The port rate of an aggregate interface equals the total rate of its Selected member ports. Its duplex mode is the same as that of the Selected member ports. For more information about the states of member ports in an aggregation group, see "Aggregation states of member ports in an aggregation group."