NIS Architecture

NIS uses a client-server arrangement. NIS servers provide services to NIS clients. The principal server is called a master server, and for reliability, it can have several backup servers 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.

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

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 also provides a forwarding service that forwards host lookups to DNS if the information cannot be found in an NIS map. The Oracle Solaris system also allows you to set up the name service switch service so that hosts lookup requests can be directed in the following ways:

• To access only DNS

• To access DNS, but if a host is not found in DNS, then access NIS

• To access NIS, but if a host is not found by NIS, then access DNS

For maximum interoperability, DNS is the recommended service for host lookups. See Chapter 2, About the Name Service Switch for details.