vSAN requires that the virtual machines deployed on the vSAN datastores are assigned at least one storage policy. When provisioning a virtual machine, if you do not explicitly assign a storage policy to the virtual machine the vSAN Default Storage Policy is assigned to the virtual machine.

The default policy contains vSAN rulesets and a set of basic storage capabilities, typically used for the placement of virtual machines deployed on vSAN datastores.

Table 1. vSAN Default Storage Policy Specifications

Specification

Setting

Primary level of failures to tolerate

1

Number of disk stripes per object

1

Flash read cache reservation, or flash capacity used for read cache

0

Object space reservation

0

Note:

Setting the Object space reservation to zero means that the virtual disk will be thin provisioned, by default.

Force provisioning

No

You can review the configuration settings for the default virtual machine storage policy from the vSphere Web Client when you navigate to the VM Storage Policies > vSAN Default Storage Policy > Manage > Rule-Set 1: VSAN.

For best results, consider creating and using your own VM storage policies, even if the requirements of the policy are same as those defined in the default storage policy. For information about creating a user-defined VM storage policy, see Define a Virtual Machine Storage Policy for vSAN.

When you assign a user-defined storage policy as the default policy to a datastore, vSAN automatically removes the association to the default storage policy and applies the settings for the user-defined policy on the specified datastore. At any point, you can assign only one virtual machine storage policy as the default policy to the vSAN datastore.

Characteristics

The following characteristics apply to the vSAN Default Storage Policy.

  • The vSAN default storage policy is assigned to all virtual machine objects if you do not select any other vSAN policy when you provision a virtual machine, that is when the VM Storage Policy field is set to Datastore default on the Select Storage page. For more information about using storage policies, see the vSphere Storage documentation.

    Note:

    VM swap and VM memory objects receive the vSAN Default Storage Policy with Force provisioning set to Yes.

  • The vSAN default policy only applies to vSAN datastores. You cannot apply the default storage policy to non-vSAN datastores, such as NFS or a VMFS datastore.

  • Because the default virtual machine storage policy is compatible with any vSAN datastore in the vCenter Server, you can move your virtual machine objects provisioned with the default policy to any vSAN datastore in the vCenter Server.

  • You can clone the default policy and use it as a template to create a user-defined storage policy.

  • You can edit the default policy, if you have the StorageProfile.View privilege. You must have at least one vSAN enabled cluster that contains at least one host. VMware highly recommends that you do not edit the settings of the default storage policy.

  • You cannot edit the name and description of the default policy, or the vSAN storage provider specification. All other parameters including the policy rules are editable.

  • You cannot delete the default policy.

  • The default storage policy is assigned when the policy that you assign during virtual machine provisioning does not include rules specific to vSAN.