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This section of the Configuring and Managing MPE/iX Internet Services manual
assumes that the reader has prior experience with DNS BIND as implemented on
other operating systems, or has familiarity with the concepts involved. There
are a number of good textbooks available on this subject to which the reader
is recommended — the following is a brief overview of a sophisticated
system.
The Domain Name System is a distributed and structured directory of
information. One of its more frequent uses is the naming of host machines. A
DNS host name will consist of several fields separated by dots, for example:
quasar.india.hp.com.
The host quasar exists in the domain india, which itself is
a subdomain of hp, which is a subdomain of com, which is a
subdomain of the root domain (identified as ".").
Abstract
With this structured naming convention, the responsibility for maintaining
accurate database information for a name domain can be delegated to a server
which is managed by the organization who owns that domain. for example, DNS
server hosts within HP maintain information about hp.com. Queries
for names inside the domain hp.com will be referred to that server by
servers in other domains. Within HP, the responsibility for
india.hp.com can also be delegated to another local DNS server.
The way this information is accessed is through client programs or code
routines called "resolvers". When a program on a client host needs to obtain
information about a domain, it will send a message to the local DNS server
host. If the local server has this information, it will send back a reply
immediately. If the local server does not have this information, it will
research by sending queries to other servers, following the Domain Name System
structure. Once the local server has found an answer for the client, it will
then reply, but will also cache what it has learned in order to respond more
speedily to subsequent queries.
Before MPE/iX 6.0, hosts running MPE/iX were able to make DNS queries of
servers running on other machines and operating systems. Now a full
implementation of the server code has been introduced. DNS BIND/iX will enable
your MPE/iX host to act as a DNS server, both responding to queries (from
clients and other servers) as well as communicating with other DNS servers on
the local network and the Internet.
DNS BIND/iX on MPE/iX 6.0 is an implementation of BIND version 8.1.1, which
has introduced many new features since the more commonly used version 4.9.4,
(with which the majority of experienced DNS users will be familiar).
This is the latest version of BIND, 8.1.1. with features like:
-
DNS Dynamic updates
-
DNS change notification
- completely new configuration syntax
- flexible and categorized logging system
- more efficient zone transfers
The package contains a host of utilities and administration tools:
-
nslookup — query Internet name servers interactively
-
dig — Domain Information Groper
- host — look up host names using domain server
- addr — get address of host
- dnsquery — give all the DNS details and Mail exchange records
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