In vSphere, Storage Policy Based Management (SPBM) plays a major role by helping to align storage with application demands of your virtual machines. It provides a storage policy framework that serves as a single unified control panel across a broad range of data services and storage solutions.

As an abstraction layer, SPBM abstracts storage services delivered by Virtual Volumes, vSAN, I/O filters, or other storage entities.

Rather than integrating with each individual type of storage and data services, SPBM provides a universal framework for different types of storage entities.

The graphic shows the SPBM layer as an abstraction layer above the datastores and I/O filters.

SPBM offers the following mechanisms:

  • Advertisement of storage capabilities and data services that storage arrays and other entities, such as I/O filters, offer.
  • Bidirectional communications between ESXi and vCenter Server on one side, and storage arrays and entities on the other.
  • Virtual machine provisioning based on VM storage policies.

About Virtual Machine Storage Policies

Virtual machine storage policies are essential to virtual machine provisioning through SPBM. The policies control which type of storage is provided for the virtual machine and how the virtual machine is placed within storage. They also determine data services that the virtual machine can use.

vSphere offers default storage policies. See Default Storage Policies in vSphere.

In addition, you can define policies and assign them to the virtual machines. See Workflow for vSphere VM Storage Policies.

You use the VM Storage Policies interface to create a storage policy. When you define the policy, you specify various storage requirements for applications that run on the virtual machines. You can also use storage policies to request specific data services, such as caching or replication, for virtual disks.

You apply the storage policy when you create, clone, or migrate the virtual machine. After you apply the storage policy, the SPBM mechanism assists you with placing the virtual machine in a matching datastore. In certain storage environments, SPBM determines how the virtual machine storage objects are provisioned and allocated within the storage resource to guarantee the required level of service. The SPBM also enables requested data services for the virtual machine and helps you to monitor policy compliance.