You can create a stretched cluster that spans two geographic locations (or sites). Stretched clusters enable you to extend the Virtual SAN datastore across two sites to use it as stretched storage. The stretched cluster continues to function if a failure or scheduled maintenance occurs at one site.
Introduction to Stretched Clusters Stretched Cluster Design Considerations Best Practices for Working with Stretched Clusters Network Design for Stretched Clusters Configure Virtual SAN Stretched Cluster Change the Preferred Fault Domain Replace the Witness Host Deploying a Virtual SAN Witness Appliance ESXi host as a witness host, you can deploy the Virtual SAN witness appliance. The appliance is a preconfigured virtual machine that runs ESXi and is distributed as an OVA file. Configure Network Interface for Witness Traffic Convert a Stretched Cluster to a Standard Virtual SAN Cluster
