To ensure high performance and availability, vSAN clusters must meet certain bandwidth and network latency requirements.

The bandwidth requirements between the primary and secondary sites of a vSAN stretched cluster depend on the vSAN workload, amount of data, and the way you want to handle failures. For more information, see VMware vSAN Design and Sizing Guide.

Table 1. Bandwidth and Latency Requirements

Site Communication



Site to Site

Minimum of 10 Gbps

Less than 5 ms latency RTT.

Site to Witness

2 Mbps per 1000 vSAN components

  • Less than 500 ms latency RTT for 1 host per site.
  • Less than 200 ms latency RTT for up to 10 hosts per site.
  • Less than 100 ms latency RTT for 11-15 hosts per site.