See "FNS and Files-Based Naming" for overview and background information relating to FNS and files.
FNS provides the XFN interface for performing basic naming and attribute operations using local files as the naming service.
FNS stores bindings for enterprise objects in files which are located in a /var/fn directory which is normally NFS mounted on each machine. These FNS files store bindings for the following enterprise namespaces:
Organization which provides a namespace for naming objects relative to the entire enterprise. When local files are the underlying naming service, there is a single organizational unit context that represents the entire system. This organization unit context is always identified in FNS as org//.
Hosts namespace which correspond to the /etc/hosts file. FNS provides a context for each host in the /etc/hosts file.
Users namespace which correspond to the /etc/passwd file. FNS provides a context for each user in the /etc/passwd file.
Sites namespace which allows you to name geographical sites relative to the organization, hosts, and users.
Services namespace which allows you to name services such as a printer service and calendar service relative to the organization, hosts, and users.
FNS provides contexts which allow other objects to be named relative to these five namespaces.
The FNS fncreate command creates the FNS files in the /var/fn directory of the machine on which the command is run. To run fncreate, you must have super-user privileges on that machine. Based on UNIX user IDs, individual users are allowed to modify their own contexts, bindings, and attributes using FNS commands.