System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP)

NIS Architecture

NIS uses a client-server arrangement. NIS servers provide services to NIS clients. The principal servers are called master servers, and for reliability, they have backup, or slave servers. Both master and slave servers use the NIS information retrieval software and both store NIS maps.

NIS uses domains to arrange the machines, users, and networks in its namespace. However, it does not use a domain hierarchy; an NIS namespace is flat.

Diagram shows 192.44.0.0 having an unidentified hierarchical
structure.

Thus, this physical network would be arranged into one NIS domain.

Diagram shows 192.44.0.0 organized in a flat NIS namespace.

An NIS domain cannot be connected directly to the Internet using just NIS. However, organizations that want to use NIS and also be connected to the Internet can combine NIS with DNS. You can use NIS to manage all local information and use DNS for Internet host lookup. NIS provides a forwarding service that forwards host lookups to DNS if the information cannot be found in an NIS map. The Solaris system also allows you to set up the nsswitch.conf file so that hosts lookup requests go only to DNS, or to DNS and then NIS if not found by DNS, or to NIS and then DNS if not found by NIS. See Chapter 2, The Name Service Switch (Overview) for details.