You are reviewing a new data center design for a customer. They chose to leverage a tunnel- based overlay technology for quick deployment and multitenant security. Which design concern can affect…

Nonoverlapping IP address space is a routing correctness requirement for multitenant overlays but does not directly cause an availability outage in the way that MTU misconfiguration does.

Tunnel-based overlay protocols (VXLAN adds approximately 50 bytes, GRE adds approximately 24 bytes) increase the effective packet size beyond the standard 1500-byte Ethernet MTU. If underlay interfaces are not configured to support jumbo frames (typically 1600-9216 bytes), encapsulated packets that exceed the underlay MTU will be either fragmented - causing performance degradation - or dropped if the DF bit is set, resulting in application outages and availability failures across the data center fabric.

Reviewing common paths on underlay links addresses redundancy and load balancing, which is a resilience concern but not a fundamental overlay-technology-specific availability issue.

Spanning Tree Protocol root bridge placement is relevant to Layer 2 underlay designs but is not applicable to tunnel-based overlay networks, which operate above Layer 2 and do not rely on STP.