Implementing Link Aggregation on a Cisco Wireless LAN Controller

D.

Link aggregation is a technique used to combine multiple physical links into a single logical link to increase bandwidth and redundancy. On a Cisco Wireless LAN Controller (WLC), link aggregation can be implemented using EtherChannel.

To configure link aggregation on a Cisco WLC, the following steps can be taken:

1. Physically connect the WLC to the switch using two or more Ethernet ports.

2. Log in to the WLC using the command-line interface (CLI) or the web-based graphical user interface (GUI).

3. Navigate to the EtherChannel configuration page.

4. Select the mode of EtherChannel, which can be either active or passive. In active mode, the WLC actively negotiates with the switch to form an EtherChannel. In passive mode, the WLC waits for the switch to initiate the negotiation.

5. Specify the ports to include in the EtherChannel.

6. Configure the EtherChannel load balancing algorithm. The WLC supports a number of load balancing algorithms, including source IP address, destination IP address, and round-robin.

7. Enable the EtherChannel.

Once link aggregation is enabled on the WLC, it provides the following benefits:

• Increased bandwidth: Link aggregation combines multiple physical links into a single logical link, which provides increased bandwidth.

• Redundancy: Link aggregation provides redundancy in case one of the physical links fails.

• Load balancing: The WLC can distribute traffic across multiple physical links using the configured load balancing algorithm.

Regarding the given answer choices:

A. The EtherChannel must be configured in mode active: This statement is partially correct. While active mode is one of the options for configuring EtherChannel, passive mode is also available.

B. When enabled, the WLC bandwidth drops to 500 Mbps: This statement is not correct. Enabling link aggregation on the WLC should not reduce the bandwidth.

C. To pass client traffic, two or more ports must be configured: This statement is correct. To implement link aggregation on a WLC, two or more physical ports must be used.

D. One functional physical port is needed to pass client traffic: This statement is not correct. While it is possible to use a single port for client traffic, implementing link aggregation provides increased bandwidth and redundancy.