Throughout the course of administering your vSphere/VSAN infrastructure, you may find that you wish to change a storage policy and the VMs associated with it. For example, you may want to change the amount of a VM that is thick-provisioned, or you may want to modify a policy so that it uses more stripes or provides a greater degree of fault tolerance.
By modifying an existing policy, you will cause these changes to cascade down to all VMs or VM disks that use the policy; thus, affecting many changes at once.
You should be logged into vSphere Web Client as an administrator or a user authorized to modify VM storage policies and VMs.
From vSphere Web Client, navigate to Home | VM Storage Policies.
Highlight the policy that you wish to modify, and then click the Edit button:
If you wish to modify the name or description, please do so, and then click Rule-Set 1.
Add the capability that you wish to use or modify one of the existing settings...