Service Names
Service names correspond to, and are determined by, service applications. The service context must be named relative to an organization, user, host, or site context. For example:
org//service/printer names the organization's printer service.
host/deneb/service/printer names the printer service associated with the machine deneb.
host/deneb/service/printer/Sparc-2 names the printer associated with the machine deneb.
user/charlie/service/calendar names the user charlie's calendar service.
site/conf_pine.bldg-7.alameda/service/calendar names the calendar service for the conf_pine conference room in Building 7 at the Alameda site.
File Names
File system names correspond to file names. For example:
host/altair/fs/etc/.login names the .login file on the machine altair.
user/prasad/fs/projects/96draft.doc names the file 96draft.doc in the user prasad's projects directory.
Getting Started
To begin using FNS with your underlying name service, you run the fncreate command.
The fncreate command recognizes the underlying naming service in which FNS contexts are to be created (such as, NIS+, NIS, or files). To specify a specific naming service, you must run the fnselect command as explained in "Designating a Non-Default Naming Service".
Designating a Non-Default Naming Service
By default:
If fncreate is executed on a machine that is an NIS+ client or server, the FNS namespace will be set up in NIS+. (See "How to Replicate FNS Under NIS+" if you want or need to designate some other machine as an FNS NIS+ master server.)
If the machine is an NIS client, the namespace will be set up in NIS.
If the machine is neither, the namespace will be set up in the machine's /var/fn directory. When your underlying naming system is files-based, the common practice is to create /var/fn by running fncreate on each machine. It is possible however to create /var/fn on one machine and export it by NFS to be mounted by other clients.
You can also explicitly specify a non-default target naming service by using the fnselect command. For example the following command selects the target naming service to be NIS.
# fnselect nis |
Creating the FNS Namespace
Once the naming service has been selected either using the default policy or explicitly via fnselect, you can execute the following command to create the FNS namespace:
# fncreate -t org org// |
This creates all the necessary contexts for users and hosts in the corresponding naming service.
NIS+ Considerations
When your primary enterprise-level naming service is NIS+, take into account the following points.
NIS+ Domains and Subdomains
The command syntax shown above creates the FNS namespace for the root NIS+ domain. To specify a domain other than the root, add the domain name between the double slashes, as in:
# fncreate -t org org/sales.doc.com./ |
Note the trailing dot after the fully qualified sales.doc.com. domain name.
Space and Performance Considerations
The fncreate commands creates NIS+ tables and directories in the ctx_dir directory. The ctx_dir directory object resides at the same level as the NIS+ groups_dir and org_dir directory objects of the domain.
With a large domain, the additional space required on the NIS+ server could be substantial and in a large installation performance might be improved by using separate servers for FNS and the standard NIS+ tables. See for information on how to use separate servers for FNS and NIS+.
In a large, or mission-critical domain, FNS service should be replicated. See "Replicating FNS Service"for information on how to replicate FNS service.
NIS+ Security Requirements
The user who runs fncreate and other FNS commands is expected to have the necessary NIS+ credentials.
The environment variable NIS_GROUP specifies the group owner for the NIS+ objects created by fncreate. In order to facilitate administration of the NIS+ objects, NIS_GROUP should be set to the name of the NIS+ group responsible for FNS administration for that domain prior to executing fncreate and other FNS commands.
Changes to NIS+ related properties, including default access control rights, could be effected using NIS+ administration tools and interfaces after the context has been created. The NIS+ object name that corresponds to an FNS composite name can be obtained using fnlookup and fnlist, described later in this document.
NIS Considerations
The fncreate command must be executed by superuser on the NIS system that will serve as the NIS master server for the FNS maps.
The NIS maps used by FNS are stored in /var/yp/domainname.
Any changes to the FNS information can only be done by the superuser on the FNS NIS master server using FNS commands.
Files Considerations
When using fncreate with the -t org option to create your FNS namespace, the command must be executed by superuser on the machine that owns the file system on which /var is located. The files used by FNS are stored in the /var/fn directory.
Once users' contexts are created, users are allowed to modify their own contexts based on their UNIX credentials.
If exported, the file system /var/fn can be mounted by other systems to access the FNS namespace.
Browsing the FNS Namespace
Once the namespace has been set up, you can browse using the following commands:
fnlist to list context contents (see "Listing Context Contents")
fnlookup to display the bindings of a composite name (see "Displaying the Bindings of a Composite Name").
fnattr to show the attributes of a composite name (see "Showing the Attributes of a Composite Name").