To set up a vSAN HCI Mesh, specific network requirements must be met between the client and server clusters. The round-trip time (RTT) latency must be less than 5 milliseconds. Additionally, a minimum of 10 Gbps network bandwidth is required for the vSAN network traffic. Option A correctly identifies the critical 5ms latency threshold. While network redundancy is a strongly recommended best practice for production environments to ensure high availability and is part of the vSAN network design guides, the latency value is a strict, officially documented requirement. Option A is the only choice that presents a correct value for a primary network requirement.

B. vSAN Enterprise License and 1 Gbps Networking

This is incorrect because the minimum network bandwidth requirement for vSAN HCI Mesh is 10 Gbps. 1 Gbps is insufficient and unsupported.

C. Latency of 10 milliseconds and bandwidth of 10 Gbps

This is incorrect because the maximum supported RTT latency is less than 5ms. A latency of 10ms is double the supported threshold and would lead to an unsupported configuration.

D. vSAN Advanced License and bandwidth of 25 Gbps

This is incorrect because the server cluster providing the datastore requires a vSAN Enterprise or Enterprise Plus license. A vSAN Advanced license is not sufficient.

1. VMware vSAN Design Guide (vSAN 8.0 U1)

Section: Chapter 2, Designing and Sizing a vSAN Cluster > vSAN HCI Mesh > HCI Mesh Compute Cluster Considerations.

Quote/Content: "The RTT between the vSAN datastore providing cluster and the vSAN compute cluster must be less than 5ms. A minimum of 10GbE networking is required for the vSAN network." This reference confirms the =10Gbps bandwidth requirements.

2. Administering VMware vSAN 8.0 Documentation

Section: vSAN Clusters > Sharing Remote Datastores with vSAN HCI Mesh > Requirements for a vSAN HCI Mesh Cluster.

Quote/Content: "The RTT latency between the client cluster and the server cluster must be less than 5 milliseconds." and "Each host in the client cluster must have a VMkernel adapter with vSAN traffic enabled, and a 10 GbE or faster physical NIC." This source validates the answers for both latency and bandwidth.

3. Dell VxRail 7.0 Network Planning Guide

Section: Network requirements > vSAN network requirements.

Quote/Content: "For all-flash configurations, Dell Technologies recommends a minimum of 10 GbE for the vSAN network. For optimal performance, Dell Technologies recommends 25 GbE or higher." While not specific to HCI Mesh, this establishes the 10 GbE baseline for modern VxRail/vSAN, invalidating the 1 GbE option. HCI Mesh requirements build upon this baseline.