300-365 Question #17: Real Exam Question with Answer & Explanation

The correct answer is D: The client context is copied from controller WLC_1 to controller WLC_2. The result is that WLC_1. When a client roams between controllers in the same mobility group to a WLC that lacks the client's home VLAN interface, Layer 3 inter-controller roaming occurs. WLC_1 retains the anchor role and WLC_2 acts as the foreign controller, tunneling client traffic back to WLC_1.

Mobility Deployment

Question

Controllers WLC_1 and WLC_2 are in the same mobility group. A wireless client that does not have the same VLAN interface roams from WLC_1 to WLC_2. What happens to the client roaming?

Options

AThe client context is deleted in controller WLC_1, and a new client context is created in WLC_2 to
BThe client context is moved from controller WLC_1 to controller WLC_2. The result is that the
CThe client context is copied from controller WLC_1 to controller WLC_2. The result is that WLC_1
DThe client context is copied from controller WLC_1 to controller WLC_2. The result is that WLC_1

Explanation

When a client roams between controllers in the same mobility group to a WLC that lacks the client's home VLAN interface, Layer 3 inter-controller roaming occurs. WLC_1 retains the anchor role and WLC_2 acts as the foreign controller, tunneling client traffic back to WLC_1.

Common mistakes.

A. Deleting the context on WLC_1 and creating a new context on WLC_2 describes either a full re-association or a failed roam event, not the anchor-foreign mobility tunnel mechanism used in Layer 3 roaming.
B. Fully moving the client context from WLC_1 to WLC_2 describes a Layer 2 intra-VLAN roam where the same VLAN exists on the destination controller; because the VLAN is absent on WLC_2, WLC_1 cannot release its anchor role.
C. Choice C also describes a context copy but does not correctly characterize the anchor-foreign relationship or the traffic tunneling behavior; option D accurately reflects that WLC_1 retains anchor duties and forwards traffic from the wired side.

Concept tested. Layer 3 inter-controller roaming anchor and foreign WLC roles

Reference. https://www.cisco.com/c/en/us/td/docs/wireless/controller/8-5/config-guide/b_cg85/mobility.html

Topics

#inter-controller roaming#mobility groups#client context#VLAN mismatch

Community Discussion

No community discussion yet for this question.

Full 300-365 Practice