There are a number of commands to verify an EtherChannel configuration. First, the show interface port-channel command displays the general status of the port channel interface. In Figure 1, the Port Channel 1 interface is up.

When several port channel interfaces are configured on the same device, use the show etherchannel summary command to simply display one line of information per port channel. In Figure 2, the switch has one EtherChannel configured; group 1 uses LACP.

The interface bundle consists of the FastEthernet0/1 and FastEthernet0/2 interfaces. The group is a Layer 2 EtherChannel and that it is in use, as indicated by the letters SU next to the port channel number.

Use the show etherchannel port-channel command to display information about a specific port channel interface, as shown in Figure 3. In the example, the Port Channel 1 interface consists of two physical interfaces, FastEthernet0/1 and FastEthernet0/2. It uses LACP in active mode. It is properly connected to another switch with a compatible configuration, which is why the port channel is said to be in use.

On any physical interface member of an EtherChannel bundle, the show interfaces etherchannel command can provide information about the role of the interface in the EtherChannel, as shown in Figure 4. The interface FastEthernet 0/1 is part of the EtherChannel bundle 1. The protocol for this EtherChannel is LACP.

Use the Syntax Checker in Figure 5 to verify EtherChannel on switch S1.