Policy Attributes
NetBackup for OpenStack's tenant driven backup service gives tenants control over backup policies. However, sometimes it may be too much control to tenants and the cloud administrators may want to limit what policies are allowed by tenants. For example, a tenant may exceed its quota by performing full backups at a very high frequency. If every tenant was to pursue such backup policy, it may affect the resource limits set on the cloud infrastructure. Instead, if the cloud administrator can define predefined backup policies and each tenant is only limited to those policies then cloud administrators can exert better control over backup service.
Policy is similar to nova flavor where a tenant cannot create arbitrary instances. Instead, each tenant is only allowed to use the nova flavors published by the admin.