VXLAN

D.

VXLAN (Virtual Extensible LAN) is a network virtualization technology that extends Layer 2 networks over a Layer 3 network. It is commonly used in data center environments to create overlay networks that enable multi-tenancy and network virtualization.

Now, let's look at each statement to determine which one is true:

A. Control-plane traffic traverses the underlay network.

This statement is partially true. The VXLAN control plane traffic is used to establish and maintain the VXLAN overlay network, which includes exchanging MAC address information between VXLAN VTEPs (VXLAN Tunnel Endpoints). This traffic can be sent over the underlay network or dedicated management network, but it is not typically sent over the overlay network.

B. Control-plane traffic traverses the overlay network.

This statement is false. As mentioned in the previous statement, the VXLAN control plane traffic is not typically sent over the overlay network.

C. Data-plane traffic traverse the overlay network.

This statement is true. In VXLAN, data-plane traffic (user traffic) is encapsulated with a VXLAN header and sent over the overlay network between VXLAN VTEPs. This enables communication between virtual machines (VMs) that are connected to different physical hosts within the same VXLAN network.

D. Data-plane traffic traverse the underlay network.

This statement is partially true. The encapsulated VXLAN traffic is sent over the underlay network between VXLAN VTEPs. However, the actual user traffic is encapsulated within the VXLAN header and is not visible to the underlay network.

Therefore, the correct statement about VXLAN is:

C. Data-plane traffic traverse the overlay network.