6.0.1

About Datastore-Specific and Common Rule Sets
A storage policy can include one or several rule sets that describe requirements for virtual machine storage
resources. It can also include common rules.
If common rules are not available in your environment or not dened, you can create a policy that includes
datastore-specic rule sets. To dene a policy, one rule set is required. Additional rule sets are optional.
Multiple rule sets allow a single policy to dene alternative selection parameters, often from several storage
providers.
A single rule set contains one or several rules. Each rule can be based on a single underlying data service
that a storage entity guarantees. The rule describes a specic quality or quantity that the storage resource
must provide. You can also reference user-dened datastore tags in the rules. One datastore-specic rule set
can include rules from only a single storage entity.
The relationship between all rule sets within a policy is dened by the Boolean operator OR, whereas the
relationship between all rules within a single rule set is dened by AND. Meeting all the rules of any one
rule set is sucient to satisfy the entire policy. Each rule set represents an equally acceptable set of
constraints.
Virtual machine storage policy
Rule set 1
rule 1_1
and
rule 1_2
and
rule 1_3
or
Rule set 2
rule 2_1
and
rule 2_2
Rule set 3
rule 3_1
and
rule 3_2
and
rule 3_3
or
If common rules are enabled, the policy is required to include either common rules or at least one datastore-
specic rule set. If you dene both common rules and datastore-specic rules, the storage policy matches
datastores that satisfy all common rules and all rules in at least one of the rule sets.
Working with Virtual Machine Storage Policies
The entire process of creating and managing storage policies typically includes several steps. Whether you
must perform a specic step might depend on the type of storage or data services that your environment
oers.
1 If you use storage policies with storage providers, verify that an appropriate storage provider is
registered. Entities that require storage providers include Virtual SAN, Virtual Volumes, and I/O lters
that provide additional software data services to virtual machines.
See Chapter 25, “Using Storage Providers,” on page 277.
2 Apply storage tags to datastores. See “Assign Tags to Datastores,” on page 231.
3 Create storage policies by dening requirements for applications that run on a virtual machine. See
“Dene a Storage Policy for a Virtual Machine,” on page 232.
vSphere Storage
230 VMware, Inc.