If you plan to use vSAN as the principal storage type for a VI workload domain in VMware Cloud Foundation, you must determine the size of the compute and storage resources for the vSAN storage, the configuration of the network carrying vSAN traffic. For multiple availability zones, you extend the resource size and determine the configuration of the vSAN witness host.
Because you determine storage type and SLA for customer workloads according the business requirements of your organization, this design provides no specific guidance on the size and storage policy for virtual machines in the VI workload domain.