Home » Cisco » 200-355 » Which two statements best describe the LAG configuration between a Cisco WLC and a Cisco Catalyst switch?
Which two statements best describe the LAG configuration between a Cisco WLC and a Cisco Catalyst switch? (Choose two.)
A. The Catalyst switch should be configured for PAgP.
B. The Catalyst switch should be configured only for Layer 2 load balancing.
C. The Catalyst switch should be configured for “on” mode.
D. The Cisco WLC relies on the connected switch to perform the load-balance of traffic.
E. The Cisco WLC aggregates multiple management interfaces into a single virtual interface.
Correct Answer: CD
Explanation/Reference:
Explanation:
Restrictions for Link Aggregation
You can bundle all eight ports on a Cisco 5508 Controller into a single link.
Terminating on two different modules within a single Catalyst 6500 series switch provides redundancy and ensures that connectivity between the switch and the controller is maintained when one module fails. The controller’s port 1 is connected to Gigabit interface 3/1, and the controller’s port 2 is connected to Gigabit interface 2/1 on the Catalyst 6500 series switch. Both switch ports are assigned to the same channel group.
LAG requires the EtherChannel to be configured for ‘mode on’ on both the controller and the Catalyst switch.
Once the EtherChannel is configured as on at both ends of the link, the Catalyst switch should not be configured for either Link Aggregation Control Protocol (LACP) or Cisco proprietary Port Aggregation Protocol (PAgP) but be set unconditionally to LAG. Because Cisco WLC relies on the connected switch to perform the load-balance of traffic, the controller does not answer tonegotiation frames and the LAG is not formed if a dynamic form of LAG is set on the switch.
Additionally, LACP and PAgP are not supported on the controller.
http://www.cisco.com/c/en/us/td/docs/wireless/controller/7-4/configuration/guides/consolidated/b_cg74_CONSOLIDATED/b_cg74_CONSOLIDATED_chapter_0100011.html
