TCP/IP Configuration and Management Manual

Configuration Reference
TCP/IP Configuration and Management Manual—427132-004
A-3
Domain Name Server (DNS)
boundaries. The DNS allows the authority for this information to be delegated to the
organizations on the network that are responsible for it.
The DNS, as defined in RFCs 1032, 1033, 1034, and 1035, allows a network to be
divided into a hierarchy of domains. The name space is organized as a tree structure
according to organizational or administrative boundaries. Each node (called a domain)
is given a label, and the name of the domain is derived by concatenating all the labels
of the domains from the root of the tree down to the current domain. A label need only
be unique within its domain.
The whole name space is partitioned into several areas called zones, each starting at a
domain and extending down to the leaf domains or to domains where other zones
start. Zones usually represent administrative boundaries. The following example shows
an address for a host at KentComm:
guru.develop.KentComm.com
com is the top level domain for commercial organizations. KentComm is a subdomain
of com, and develop is a subdomain of KentComm. The host itself, guru, belongs to
the domain develop.
The program file that implements the DNS is $SYSTEM.ZTCPIP.NAMED, so the DNS
is sometimes referred to as NAMED. The basic function of the DNS is to provide
information about network objects by answering queries. The information provided by
the DNS includes name-to-address mapping, address-to-name mapping, mailbox
information, and machine hardware/software information.
For more detailed information on domain names, refer to RFC 1034 and RFC 1035
available from the DDN Network Information Center. Also, refer to the book TCP/IP
Illustrated by W. Richard Stevens, Prentice Hall, 1994.
The Domain Name Server (DNS) was ported from BSD BIND 4.8.
Types of Domain Name Servers
There are four basic types of Domain Name Servers:

Master

Caching-Only

Remote

Slave
Master Server
A master server for a domain is the authority for that domain. This server maintains all
the data corresponding to its domain. Each domain should have at least two master
Note. You should read RFCs 819, 920, 974, 1032, 1033, 1034, 1035, and 1101 before you
attempt to configure the server.