A network administrator enables Link Aggregation (LAG) on a Cisco Wireless LAN Controller (WLC) to combine its physical distribution system ports into a single logical interface. How must the connected ports on the upstream switch be configured to establish this link aggregation successfully?
- Configured as a static EtherChannel using the command channel-group mode on without dynamic negotiation protocols.Answer
- BConfigured with dynamic LACP using channel-group mode active to negotiate port channel parameters with the controller.
- CConfigured as individual access ports that automatically switch to local switching mode when controller LAG is activated.
- DConfigured with different native VLANs across the member interfaces to segregate control and data traffic.
Answer
The switch ports connected to the Wireless LAN Controller must be configured as a static EtherChannel using the channel-group mode on command.
When Link Aggregation (LAG) is enabled on a Cisco Wireless LAN Controller, all physical distribution system ports are bundled into a single logical channel that carries all VLANs as an 802.1Q trunk. Because the controller does not use dynamic negotiation protocols such as LACP or PAgP, the corresponding connected interfaces on the adjacent switch must be configured as a static EtherChannel using the `channel-group mode on` command.
Step-by-Step Solution
Key Concept
WLC Link Aggregation (LAG) Switchport Configuration