For a successful EtherChannel configuration, what link characteristics must match on both ends?

For a successful EtherChannel configuration, the link characteristics that must match on both ends include duplex, speed, and switchport mode.

Duplex settings must be the same (either both full or both half) to ensure that data can flow without collisions and interruptions. If one end is set to half duplex while the other is full duplex, this can result in packet loss and other communication issues.

Speed must also be identical on both ends of the EtherChannel. Mismatched speeds can lead to the inability of the EtherChannel to form correctly and ultimately affect network performance. For example, if one interface operates at 100 Mbps and the other at 1 Gbps, the EtherChannel cannot become operational, resulting in traffic not being balanced effectively across the links.

Switchport mode refers to the type of port configuration, such as access or trunk mode. For EtherChannel to be successfully established, both ports must be set to the same switchport mode. If one port is configured as an access port while the other is configured as trunk, the EtherChannel will not form.

This explanation highlights the significance of each of these settings in the context of EtherChannel formation and functionality, making it clear why matching duplex, speed, and switchport mode is critical.