1. A computer program product comprising one or more non-transitory computer readable storage media storing instructions translatable by one or more processors to perform: receiving a request configured to affect change to file system resources in a network file system including an interface extending across the network to enable access to files arranged in directories on the network, wherein the request comprises data and an operation for one or more from a group of the files and directories; consulting a policy rule base comprising one or more policy rules to determine if the request comprises information that triggers application of a policy rule, wherein the policy rule includes a pattern defining a boolean expression for evaluation of a set of metadata and a rule action that is applicable to the request with respect to policies for the network file system and defining a modification for the request, and wherein consulting the policy rule base comprises: determining from the request the operation and a filesystem object on which the operation is to be performed; and evaluating each of the patterns of the policy rules utilizing metadata corresponding to the filesystem object to determine triggering of application of the policy rule; in response to triggering application of the policy rule, applying the rule action to the request in order to modify the operation of the request in accordance with the policy rule; and forwarding the modified request to the network file system to affect change to the file system resources in accordance with the policies for the network file system.