We strongly recommend you should firstly configure LAG feature on switch before other functions like VLAN, STP, QoS, GVRP, port attributes, MAC Address Learning mode and other associated settings. The LAG group is a logical link, and LAG’s configuration for these features has a higher priority than configuration for ports that LAG includes. LAGs can be used to directly connect two switches when the traffic between them requires high bandwidth and reliability, or to provide a higher-bandwidth connection to a public network. Management functions treat a LAG as if it were a single physical port. You can include a LAG in a VLAN. You can configure more than one LAG for a given switch.