Solaris Naming Administration Guide

Default FNS Namespaces

There are seven namespaces supplied with FNS:

Organizational Unit Namespace

The organizational unit namespace provides a hierarchical namespace for naming subunits of an enterprise. Each organizational unit name is bound to an organizational unit context that represents the organizational unit. Organization unit names are identified by the prefixes org/, orgunit/, or _orgunit/. (The shorthand alias org/ is only used in the initial context, never in the middle of a compound name. See "Initial Context Bindings for Naming Within the Enterprise" and "Composite Name Examples".)

NIS+ Environment

In an NIS+ environment, organizational units correspond to NIS+ domains and subdomains.

Under NIS+, organization units must map to domains and subdomains. You must have an organizational unit for each NIS+ domain and subdomain. You cannot have "logical" organization units within a domain or subdomain. In other words, you cannot divide an NIS+ domain or subdomain into smaller organization units. Thus, if you have a NIS+ domain and two subdomains and, you must have three FNS organizational units corresponding to those three domains.

Organizational units are named using dot-separated right-to-left compound names, where each atomic element names an organizational unit within a larger unit. For example, the name org/ names an organizational unit sales within a larger unit named In this example, sales is an NIS+ subdomain of

Organizational unit names can be either fully qualified NIS+ domain names or relatively named NIS+ names. Fully qualified names have a terminal dot; relative names do not. Thus, if a terminal dot is present in the organization name, the name is treated as a fully qualified NIS+ domain name. If there is no terminal dot, the organization name is resolved relative to the top of the organizational hierarchy. For example, orgunit/ is a fully qualified name identifying the west organization unit, and _orgunit/west.sales is a relatively qualified name identifying the same subdomain.

NIS Environment

In a NIS environment there is only one organization unit per enterprise which corresponds to the NIS domain. This orgunit is named orgunit/domainname where domainname is the name of the NIS domain. For example, if the NIS domain name is, the organizational unit is org/

In an NIS environment, you can use an empty string as a shorthand for the organizational unit. Thus, org// is equivalent to org/domainname.

Files-Based Environment

There is only one FNS organization unit and no subunits when your primary enterprise-level name service is files-based. The only permitted organization unit under files-based naming is org//.

Site Namespace

The site namespace provides a geographic namespace for naming objects that are naturally identified with their physical locations. These objects can be, for example, buildings on a campus, machines and printers on a floor, conference rooms in a building and their schedules, and users in contiguous offices. Site names are identified by the prefixes site/or _site/.

In the Solaris environment, sites are named using compound names, where each atomic part names a site within a larger site. The syntax of site names is dot-separated right-to-left, with components arranged from the most general to the most specific location description. For example, _site/pine.bldg5 names the Pine conference room in building 5, while site/bldg7.alameda identifies building 7 of the Alameda location of some enterprise.

Host Namespace

The host namespace provides a namespace for naming computers. Host names are identified by the prefixes host/or _host/. For example, host/deneb identifies a machine named deneb.

Hosts are named in hostname contexts. The host context has a flat namespace and contains bindings of host names to host contexts. A host context allows you to name objects relative to a machine, such as files and printers found at that host.

In the Solaris environment, host names correspond to Solaris host names. Alias names for a single machine share the same context. For example, if the name mail_server is an alias for the machines deneb and altair, both deneb and altair will share the contexts created for mail_server.

Network resources should only be named relative to hosts as appropriate. In most cases, it is more intuitive to name resources relative to entities such as organizations, users, or sites. Dependence on host names forces the user to remember information that is often obscure and sometimes not very stable. For example, a user's files might move from one host to another because of hardware changes, file space usage, network reconfigurations, and so on. And users often share the same file server, which might lead to confusion if files were named relative to hosts. Yet if the files were named relative to the user, such changes do not affect how the files are named.

There might be a few cases in which the use of host names is appropriate. For example, if a resource is available only on a particular machine and is tied to the existence of that machine, and there is no other logical way to name the resource relative to other entities, then it might make sense to name the resource relative to the host. Or, in the case of a file system, if the files are being shared by many users it might make sense to name them relative to the machine they are stored on.

User Namespace

The user namespace provides a namespace for naming human users in a computing environment. User names are identified by the prefixes user/or _user/.

Users are named in user contexts. The user context has a single-level namespace and contains bindings of user names to user contexts. A user context allows you to name objects relative to a user, such as files, services, or resources associated with the user.

In the Solaris environment, user names correspond to Solaris login IDs. For example, _user/inga identifies a user whose login ID is inga.

File Namespace

A file namespace (or file system) provides a namespace for naming files. File names are identified by the prefixes fs/or _fs/. For example the name fs/etc/motd identifies the file motd which is stored in the /etc directory.

The file namespace is described in more detail in "FNS File Naming". and file contexts are discussed in "File Contexts Administration".

Service Namespace

The service namespace provides a namespace for services used by or associated with objects within an enterprise. Examples of such services are electronic calendars, faxes, mail, and printing. Service names are identified by the prefixes service/ or _service/.

In the Solaris environment, the service namespace is hierarchical. Service names are slash-separated (/) left-to-right compound names. An application that uses the service namespace can make use of this hierarchical property to reserve a subtree for that application. For example, the printer service reserves the subtree printer in the service namespace.

FNS does not specify how service names or reference types are chosen. These are determined by service providers that share the service namespace. For example, the calendar service uses the name _service/calendar in the service context to name the calendar service and what is bound to the name calendar is determined by the calendar service.

Service Name and Reference Registration

Sun Microsystems, Inc., maintains a registry of the names bound in the first level of the service namespace. To register a name, send an email request to, or write to:

FNS Registration Sun Microsystems, Inc., 901 San Antonio Road, Palo Alto, CA 94303

Please include a brief description of the intended use of the name and a description of the format of the reference that can be bound to that name.

Printer Namespace

The printer namespace provides a namespace for naming printers. The printer namespace is associated with (subordinate to) the service namespace. In other words, printer service and the printer namespace is one of the services in the service namespace. Printer names are identified by the prefixes service/printer or _service/printer. For example, service/printer/laser1 identifies the printer named laser1.