Virtual static groups make it possible to get the efficiency and ease of management of a dynamic group while allowing clients to interact with them as a static group.
Static groups can be easier to interact with than dynamic groups, but large static groups can be expensive to manage and require a large amount of memory to hold in the internal group cache. Directory Server provides a third type of group: a virtual static group, which references another group and provides access to the members of that group as if it was a static group.