A VM storage policy in vSphere can include one or several reusable and interchangeable building blocks, called storage policy components. Each component describes a particular data service to be provided for the virtual machine. You can define the policy components in advance and associate them with multiple VM storage policies.

You cannot assign the predefined component directly to a virtual machine or virtual disk. Instead, you must add the component to the VM storage policy, and assign the policy to the virtual machine.

The component describes one type of service from one service provider. The services can vary depending on the providers that you use, but generally belong in one of the following categories.
  • Compression
  • Caching
  • Encryption
  • Replication

When you create the storage policy component, you define the rules for one specific type and grade of service.

The following example shows that virtual machines VM1 and VM2 have identical placement requirements, but must have different grades of replication services. You can create the storage policy components with different replication parameters and add these components to the related storage policies.

Table 1. Storage Policy Components
Virtual Machine Placement Rules Storage Policy Component
VM1 requires replication every 2 hours Virtual Volumes Datastore 2-hour Replication
VM2 requires replication every 4 hours Virtual Volumes Datastore 4-hour Replication

The provider of the service can be a storage system, an I/O filter, or another entity. If the component references an I/O filter, the component is added to the host-based rules of the storage policy. Components that reference entities other than the I/O filters, for example, a storage system, are added to the datastore-specific rule sets.

When you work with the components, follow these guidelines:
  • Each component can include only one set of rules. All characteristics in this rule set belong to a single provider of the data services.
  • If the component is referenced in the VM storage policy, you cannot delete the component. Before deleting the component, you must remove it from the storage policy or delete the storage policy.
  • When you add components to the policy, you can use only one component from the same category, for example caching, per a set of rules.

Create Storage Policy Components

A storage policy component describes a single data service, such as replication, that must be provided for the virtual machine. You can define the component in advance and associate it with multiple VM storage policies. The components are reusable and interchangeable.

Procedure

  1. In the vSphere Client, open the New Storage Policy Component dialog box.
    1. Click Menu > Policies and Profiles.
    2. Under Policies and Profiles, click Storage Policy Components.
  2. Click Create Storage Policy Component.
  3. Select the vCenter Server instance.
  4. Enter a name, for example, 4-hour Replication, and a description for the policy component.
    Make sure that the name does not conflict with the names of other components or storage policies.
  5. Select the category of the service, for example, Replication.
  6. Select the service provider.
  7. Define rules for the selected category.
    For example, if you are configuring 4-hour replication, set the Recovery Point Objective (RPO) value to 4.

    For encryption based on I/O filters, set the Allow I/O filters before encryption parameter. Encryption provided by storage does not require this parameter.

    Option Description
    False (default) Does not allow the use of other I/O filters before the encryption filter.
    True Allows the use of other I/O filters before the encryption filter. Other filters, such as replication, can analyze clear text data before it is encrypted.
  8. Click OK.

Results

The new component appears in the list of storage policy components.

What to do next

You can add the component to the VM storage policy. If the data service that the component references is provided by the I/O filters, you add the component to the host-based rules of the storage policy. Components that reference entities other than the I/O filters, for example, a storage system, are added to the datastore-specific rule sets.

Edit or Clone Storage Policy Components

You can modify the existing storage policy components. You can also create a copy of the existing component by cloning it.

Procedure

  1. In the vSphere Client, navigate to the storage policy component to edit or clone.
    1. Click Menu > Policies and Profiles.
    2. Under Policies and Profiles, click Storage Policy Components.
  2. Select the component and click one of the following icons.
    Option Description
    Edit Settings When editing, you cannot change the category of the data service and the provider. For example, if the original component references replication provided by I/O filters, these settings must remain unchanged.
    Clone When cloning, you can customize any settings of the original component.
  3. Modify appropriate values, and click OK.
  4. If a VM storage policy that is assigned to a virtual machine references the policy component you edit, reapply the storage policy to the virtual machine.
    Menu Item Description
    Manually later If you select this option, the compliance status for all virtual disks and virtual machine home objects associated with the storage policy changes to Out of Date. To update configuration and compliance, manually reapply the storage policy to all associated entities. See Reapply Virtual Machine Storage Policy.
    Now Update virtual machine and compliance status immediately after editing the storage policy.