User's Manual
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Chapter 64 Configuring DNS
64.1 Overview
DNS is Domain Name System for short,DNS is a distributing database using in TCP/IP application.. It can
provide the translation of host name and IP address, some information about email and hosts.
The name DNS is used in the TCP/IP network, such as Internet,and it orientates hosts and service according
to friendly name. When the DNS name is input, the system can translate it into relative information such as
IP address.
In DNS system, DNS Resolver equals to a client of DNS Server. The application can get relative information
by accessing DNS Server. The base of this information is: getting the IP address according to a host name or
getting the host name according to a IP address.
Dynamic DNS Resolver is used in the condition of dynamic IP addresses. Dynamic DNS Resolver can register
the information about Host/address to DNS Server auotly,when the IP address changes, it can send updating
message to DNS Server and the DNS Server will update its database.
64.1.1 DNS Application
DNS has abroad application:
Provide translating host name to IP address for ping
、
telnet and traceroute.
Provide translating IP address to host name for telnet. When traceroute gets each IP
address, it can get the name of the address.
When IP address of client changes, it can update the address in primary server.
64.1.2 DNS Term
DNS Resource Record(RR):
Information, which may be empty. The set of resource information associated with a particular name is
composed of separate resource records (RRs). The order of RRs in a set is not significant, and need not be
preserved by name servers, resolvers, or other parts of the DNS.
Starting Organism of Authorization (SOA)
A record is used to designated the starting point of the area. The record contains the domain name, e-mail
address of the domain administrator and the settings about how to enable the DNS server to update the domain
data files.
Comman types of resource records:
Parameter
Description
A A host address.
CNAME Identifies the canonical name of analias.
HINFO Identifies the CPU and OS used by a host.
MX Identifies a mail exchange for the domain. See [RFC-974 for details.
NS The authoritative name server for the domain.