1. In a storage area network (SAN), the improvement comprising: one or more digital data processors each having a file system that effects access to one or more storage devices, each processor being associated with a first processor group and a second processor group hierarchically descending from the first processor group, the first processor group being associated with a first set of plural attributes defining a first file extension policy, the second processor group being associated with a second set of one or more attributes, each corresponding to and overriding a corresponding attribute in the first set, where the attributes of the second set, taken in conjunction with non-overridden attributes of the first set, define a policy for the second group, a process in communication with the digital data processors, the process effecting the display of the processor groups as a hierarchical tree, and further effecting display, for each processor group, of one or more tree nodes, each tree node identifying at least one attribute of the policy defined for that processor group.