Unlike traditional LUN and NFS based vSphere storage, the Virtual Volumes functionality does not require preconfigured volumes on a storage side. Instead, Virtual Volumes uses a storage container, which is a pool of raw storage capacity or an aggregation of storage capabilities that a storage system can provide to virtual volumes.
A storage container is a part of the logical storage fabric and is a logical unit of the underlying hardware. The storage container logically groups virtual volumes based on management and administrative needs. For example, the storage container can contain all virtual volumes created for a tenant in a multitenant deployment, or a department in an enterprise deployment. Each storage container serves as a virtual volume store and virtual volumes are allocated out of the storage container capacity.
Typically, a storage administrator on the storage side defines storage containers. The number of storage containers, their capacity and size depend on a vendor-specific implementation, but at least one container for each storage system is required.
After you register a storage provider associated with the storage system, vCenter Server discovers all configured storage containers along with their storage capability profiles, protocol endpoints, and other attributes. A single storage container can export multiple capability profiles. As a result, virtual machines with diverse needs and different storage policy settings can be a part of the same storage container.
Initially, all discovered storage containers are not connected to any specific host, and you cannot see them in the vSphere Web Client. To mount a storage container, you must map it to a virtual datastore.