In a vCloud Director environment, users can self-provision vApps to virtual data centers that contain a pool of storage capacity. The physical storage details are abstracted from the user. Precise control of where vApps reside in the physical infrastructure is removed due to provisioning responsibility shifting to the end user. Datastore sizing is a balancing act between availability, recoverability, performance, and manageability requirements. When thin provisioning, fast provisioning, or snapshots are enabled, existing VM storage requirements can grow and create out-of-space datastore conditions. Leverage vCloud Director datastore yellow and red thresholds, vSphere alarms, and other storage monitoring tools.