Linux System Administration

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Chapter 3: The Domain Name System

Editing the Configuration Files

So far, we have made a high-level exploration of the Domain Name System and

explained the parts you have to maintain. We now need to get into the details of the

configuration files so you can write them, change them, and fix them when the need

arises.

When you install BIND on Linux, the package will provide configuration files for

you; you won’t have to write every file from scratch. Figure 3-3 illustrates the basic

files. We’ll start with the named.conf file, which coordinates the whole system on

each BIND server and points to the rest.

named.conf

Recall from the section “Answering Queries” that when named receives a request it

consults its own small directory, the named.conf configuration file. This points

named to the zone file for the requested domain.

Let’s look at a simple named.conf file. If you can’t understand it at this point, just

familiarize yourself with the way it looks. We’ll break it down into its components in

a moment.

Remember, this file is typically already installed on your Linux server by default.

Depending on the distribution, named.conf can live in different directories (it’s

located at /etc/bind/named.conf for BIND 9 under Debian), and its appearance may

vary slightly. Sometimes, for example, the file comes heavily commented.

Here’s our sample named.conf. Comments follow double slash marks:

options {

pid-file ...