One of our partners was playing around with vCloud Director and noticed that they could create a Provider vDC and link it directly to an ESX Host. vCloud Director did not complain about it so they figured it would be okay. However it is a requirement for vCloud Director to have DRS. One of the reasons for this being is the fact that vCloud Director leverages resource pools to ensure tenants receive what they are entitled to.
But back to the issue, they created the Provider vDC and went on to create an Org vDC and even that worked fine… Next stop was the “Organization Network. In order to create one you will need to select a network pool at some point and for some weird reason that didn’t work. After some initial emailing back and forth I noticed they didn’t select a cluster or resource pool but an ESX host. After creating a new Provider vDC based on a vSphere Resource Pool all of a sudden everything started working. Although I cannot really say why it is exactly this part that causes an issue, I can tell you that DRS is a hard requirement and not just a suggestion!