A network engineer is deploying a new wireless LAN controller (WLC) in a campus network. The WLC must manage 200 access points across three buildings. The engineer configures the WLC with a management IP address and enables CAPWAP. However, the access points fail to join the WLC. The APs are in the same VLAN as the WLC and can ping the WLC's management IP. What is the most likely cause of the APs not joining?
Trap 1: The APs are not configured with DHCP option 43 to point to the WLC.
Incorrect because DHCP option 43 is used for APs in different subnets; since APs are in the same VLAN, they can use Layer 2 CAPWAP discovery and do not need option 43.
Trap 2: The APs are running an incompatible IOS version that does not…
Incorrect because CAPWAP is supported on most modern APs; version incompatibility would typically cause a different error, not a failure to join.
Trap 3: The APs must be assigned a static IP address to join the WLC.
Incorrect because APs can use DHCP to obtain an IP address; static IP is not a requirement for CAPWAP discovery.
- A
The WLC does not have a CAPWAP source interface configured.
Correct because the CAPWAP source interface must be configured on the WLC so that APs can discover and communicate with it. Without it, the WLC may not respond to CAPWAP discovery requests.
- B
The APs are not configured with DHCP option 43 to point to the WLC.
Why wrong: Incorrect because DHCP option 43 is used for APs in different subnets; since APs are in the same VLAN, they can use Layer 2 CAPWAP discovery and do not need option 43.
- C
The APs are running an incompatible IOS version that does not support CAPWAP.
Why wrong: Incorrect because CAPWAP is supported on most modern APs; version incompatibility would typically cause a different error, not a failure to join.
- D
The APs must be assigned a static IP address to join the WLC.
Why wrong: Incorrect because APs can use DHCP to obtain an IP address; static IP is not a requirement for CAPWAP discovery.