Overlay Versus Underlay Networks JN0-281 Practice Questions (Page 6)

Questions 26–30

1. 26foundation · easy

   What is the role of encapsulation in an overlay network?

   • ATo encrypt the original packet for security.
   • BTo replace the original packet's header with a new one, discarding the original.
   • CTo carry the original packet inside a new header so it can be transported across the underlay.
   • DTo compress the original packet to reduce bandwidth usage.
   Reveal Solution Discussion Select an answer first
2. 27foundation · easy

   Which requirement is essential for an underlay network to support overlay traffic?

   • ASupport for VLAN tagging only.
   • BDedicated physical links for each overlay network.
   • CHigh bandwidth and low latency.
   • DA flat Layer 2 topology without routing.
   Reveal Solution Discussion Select an answer first
4. 28foundation · easy

   What is the primary purpose of an underlay network in relation to an overlay network?

   • ATo replace the need for IP addressing in the data center.
   • BTo provide application-level security policies.
   • CTo provide physical transport for overlay traffic.
   • DTo create virtual network segments for tenants.
   Reveal Solution Discussion Select an answer first
5. 29foundation · easy

   How does an overlay network differ from an underlay network in terms of scalability?

   • AOverlay networks cannot scale beyond the size of a single physical switch.
   • BUnderlay networks scale more easily because they do not require IP routing.
   • CBoth overlay and underlay networks scale identically by adding virtual tunnels.
   • DOverlay networks can scale independently of the physical topology, while underlay networks require physical changes to scale.
   Reveal Solution Discussion Select an answer first
6. 30expert · hard

   A network engineer is troubleshooting a performance issue in a VXLAN environment. The underlay is a spine-and-leaf fabric with 10GbE links. Users report that large file transfers between VMs in the same VXLAN segment are slow, while small transfers are fast. What is the most likely cause of this issue?

   • AThe underlay is using OSPF, which does not support the large packet sizes required by VXLAN.
   • BThe VXLAN VNI is not configured on the spine switches, causing them to drop large packets.
   • CThe VMs are in different subnets, requiring routing through a gateway for all traffic.
   • DThe underlay MTU is set to 1500 bytes, causing fragmentation of the encapsulated VXLAN packets.
   Reveal Solution Discussion Select an answer first