Technical Library

Domain Name System

Introduction

Integration

The named.boot file can have different configurations. A standard configuration looks like:

directory				/etc
primary		zone			named.hosts
primary		in-addr.arpa zone	named.rev
primary		0.0.127.in-addr.arpa	named.local
cache		.			named.ca

The first line tells the name server which directory all the listed files will be stored in.

The second line lets the name server know that it is primary for the declared zone and that the data for this zone can be found in the named.hosts file. This file, and the others listed below it, should be named something other than what the example says.

For example, if your domain name is your-domain.com and your in-addr.arpa zone is 205.99.199.in-addr.arpa, you might want to name the files named.your-domain and named.205.99.199. This way, if you decide to provide name service for another domain or for another in-addr.arpa domain, you will have specific files that are easy to tell apart.

The third line refers to the file that maps IP addresses to host names. The name server knows that it is primary for the in-addr.arpa zone that is specified and will find data for that zone in the named.rev file.

The next line is the primary statement for the loopback domain.

The final line refers to the cache file which stores information about the root name servers.

Having covered directory, primary, and cache, there are also secondary, forwarders, and slave configurations.

The secondary configuration lets the name server know that it is secondary for the declared zone and that it will obtain information for that zone from the primary name server.

A forwarders line will list the servers to which queries can be forwarded if the name server cannot resolve a query from its own files or cache. A line from an example configuration would look like:

forwarders server IP address	another server IP address

The IP addresses of the other servers are specified so that they can be queried.

The slave command makes the name server use the name servers listed on the forwarders line and nothing else. A slave server will not contact the authoritative servers for a domain, even if the forwarding servers are non-responsive. This tends to limit name service flexibility so it is not normally used.