To use Virtual SAN, you must create a host cluster and enable Virtual SAN on the cluster.
A Virtual SAN cluster can include hosts with capacity and hosts without capacity. Follow these guidelines when you create a Virtual SAN cluster.
A Virtual SAN cluster must include a minimum of three ESXi hosts. For a Virtual SAN cluster to tolerate host and device failures, at least three hosts that join the Virtual SAN cluster must contribute capacity to the cluster. For best results, consider adding four or more hosts contributing capacity to the cluster.
Only ESXi 5.5 Update 1 or later hosts can join the Virtual SAN cluster.
All hosts in the Virtual SAN cluster must have the same on-disk format.
Before you move a host from a Virtual SAN cluster to another cluster, make sure that the destination cluster is Virtual SAN enabled.
To be able to access the Virtual SAN datastore, an ESXi host must be a member of the Virtual SAN cluster.
After you enable Virtual SAN, the Virtual SAN storage provider is automatically registered with vCenter Server and the Virtual SAN datastore is created. For information about storage providers, see the vSphere Storage documentation.