vCloud Director 5.1 supports vSphere Storage DRS when using vSphere 5.1 hosts. vSphere Storage DRS also supports fast provisioning (linked clones) in vCloud Director 5.1.

vSphere Storage DRS continuously balances storage space usage and storage I/O load, avoiding resource bottlenecks to meet service levels and increase manageability of storage at scale.

vCloud Director 5.1 recognizes storage clusters. The member datastore clusters are visible in vCloud Director, but cannot be modified from vCloud Director.

vCloud Director 5.1 utilizes vSphere Storage DRS for initial placement of virtual machines.

vCloud Director uses vSphere Storage DRS to manage space utilization and I/O load balancing. vSphere Storage DRS can help rebalance virtual machines, media, and virtual machine disks within the storage pod.

As in vCloud Director 1.x, vCloud Director 5.1 determines optimal placement between datastore clusters and standalone datastores across all vSphere instances assigned within vCloud Director.

There is a new VIM object type in the REST API named DATASTORE_CLUSTER. The datastore properties now include the member datastore list when the VIM object type is DATASTORE_CLUSTER.

vSphere Storage DRS supports fast provisioning in vCloud Director.

vSphere Storage DRS supports linked clones only with vCloud Director 5.1.

Linked clone configurations that span across datastores are not supported in vCloud Director 5.1.

vSphere Storage DRS will not recommend placement of a linked clone that would span datastores from the base disk.

vSphere Storage DRS will migrate a clone to a datastore containing a shadow virtual machine and relink the clone to the existing shadow virtual machine.

Linked clones can be migrated between VMFS3 and VMFS5 and are supported in vSphere Storage DRS. The format conversions are handled automatically at the platform level.

The logic for migrating a virtual machine is influenced by factors such as the following:

Amount of data being moved.

Amount of space reduction in the source datastore.

Amount of additional space on the destination datastore.

Linked clone decisions also depend on whether the destination datastore has a copy of a base disk or whether a shadow virtual machine must be instantiated:

Putting a linked clone on a datastore without the base disk results in more space used on the datastore as opposed to placing the clone on a disk where a shadow virtual machine already exists.

During the initial placement, vSphere Storage DRS selects a datastore that contains a shadow virtual machine so that placement results in maximum space savings. If necessary, initial placement recommendations can include evacuating existing virtual machines from the destination datastore.

If a datastore that already contains the base or a shadow virtual machine is not available, vCloud Director makes a full clone to create a shadow virtual machine in a selected datastore, and then makes linked clones in the selected datastore.

The latest model in vSphere Storage DRS takes linked clone sharing into account when calculating the effects of potential moves.

Linked clones and virtual machines that are not linked clones can reside on the same datastores.

vCloud Director does not support creation, deletion, or modification of storage pods. These tasks must be performed at the vSphere level.

vCloud Director does not support member datastore operations.

Enabling vSphere Storage DRS for the datastore clusters used with vCloud Director is not supported if vSphere hosts are pre-vSphere 5.1.