5. The method as described in claim 1 wherein the virtual machine-to-physical entity constraints are defined in one or more user-defined rules.
5. The method as described in claim 1 wherein the virtual machine-to-physical entity constraints are defined in one or more user-defined rules. 21. The computer program product as described in claim 5 wherein the hierarchical tree is defined as an XML document that models a facility as a tree of physical entities and attributes associated therewith.