After configuring a Virtual SAN cluster, an administrator using the vSphere Web Client notices that the Virtual SAN datastore is smaller than expected. The cluster contains: - Three ESXi hosts…

Virtual SAN relies heavily on proper network connectivity between all ESXi hosts via dedicated vmkernel ports to form a storage cluster and aggregate disk resources. If there is a network problem, such as misconfigured vmkernel ports, firewall issues, or network partitions, not all hosts may be able to join the vSAN cluster or contribute their disks effectively. This can result in the vSAN datastore showing only the capacity of a subset of hosts, potentially just one host's capacity (100GB HDD) if others are unreachable or partitioned.

The Virtual SAN VASA provider is responsible for Storage Policy Based Management (SPBM) capabilities, allowing vCenter to query vSAN for storage capabilities; however, its disabled state does not directly prevent the underlying vSAN datastore from aggregating the physical disk capacity from all participating hosts.

vSphere High Availability (HA) is compatible with Virtual SAN and provides virtual machine restart capabilities; enabling HA does not reduce the reported storage capacity of the vSAN datastore itself.

The vSphere Web Client (or vSphere Client) is the correct interface for managing a Virtual SAN cluster, but this statement describes the management tool rather than a technical reason for reduced datastore capacity.