Naming and Directory Services (DNS, NIS, and LDAP)

Subsequent changes in your organization would be accommodated by changes to thenetwork information structure without reorganizing the network structure.Solaris Naming ServicesThe Solaris platform provides the following naming services.■■■■■DNS, the Domain Name System (see “Description of the DNS Naming Service”on page 27)/etc files, the original UNIX ® naming system (see “Description of the /etc FilesNaming Service” on page 28)NIS, the Network Information Service (see “Description of the NIS Naming Service”on page 28)NIS+, the Network Information Service Plus (see System Administration Guide: Namingand Directory Services (NIS+))LDAP, the Lightweight Directory Access Protocol (see Part IV LDAP Naming ServicesSetup and Administration)Most modern networks use two or more of these services in combination. When morethan one service is used, the services are coordinated by the nsswitch.conf filewhich is discussed in Chapter 2.Description of the DNS Naming ServiceDNS is the naming service provided by the Internet for TCP/IP networks. DNS wasdeveloped so that machines on the network could be identified with common namesinstead of Internet addresses. DNS performs naming between hosts within your localadministrative domain and across domain boundaries.The collection of networked machines that use DNS are referred to as the DNSnamespace. The DNS namespace can be divided into a hierarchy of domains. A DNSdomain is a group of machines. Each domain is supported by two or more nameservers, a principal server and one or more secondary servers. Each server implementsDNS by running the in.named daemon. On the client’s side, DNS is implementedthrough the “resolver.” The resolver’s function is to resolve users’ queries. Theresolver queries a name server, which then returns either the requested information ora referral to another server.Chapter 1 • Naming and Directory Services (Overview) 27