LPI lists the location of named.conf in /etc. However, the location may vary across distributions. For example in the Debian Linux distribution named.conf is located in the /etc/bind directory.

This is an example named.conf file. The version below is taken from the Debian bind package (some comments removed).

options {
        directory "/var/named";

        // query-source address * port 53;

        // forwarders {
        //      0.0.0.0;
        // };
};

// reduce log verbosity on issues outside our control
logging {
        category lame-servers { null; };
        category cname { null; };
};

// prime the server with knowledge of the root servers
zone "." {
        type hint;
        file "/etc/bind/db.root";
};

// be authoritative for the localhost forward and reverse zones, and for
// broadcast zones as per RFC 1912

zone "localhost" {
        type master;
        file "/etc/bind/db.local";
};

zone "127.in-addr.arpa" {
        type master;
        file "/etc/bind/db.127";
};

zone "0.in-addr.arpa" {
        type master;
        file "/etc/bind/db.0";
};

zone "255.in-addr.arpa" {
        type master;
        file "/etc/bind/db.255";
};

// add entries for other zones below here

The Debian bind package that contains this file, will provide a fully functional caching-only name server. BIND packages of other manufacturers will provide the same functionality.

A caching-only name server resolves names, which are also stored in a cache, so that they can be accessed faster when the nameserver is asked to resolve these names again. But this is what every name server does. The difference is this is the only task a caching-only name server performs. It does not serve out zones, except for a few internal ones.

The named.conf file contains statements that start with a keyword plus a { (opening curly brace) and end with with a } (closing curly brace). The options statement is an example.

A statement may contain other statements. The forwarders statement is an example of this.

A statement may also contain things like IP addresses or file followed by a filename. These simple things must be terminated by a semi-colon (;).

All kinds of comments are allowed, e.g., // and # as end of line comments. See the named.conf(5) manual page for details.

Of the many possible entries (see named.conf(5)) inside an options statement, only the directory, forwarders, forward, version and dialup will be discussed below.

Many more options can be placed inside the options block. See the manual page.

The BIND (version 8 and 9) logging system is too elaborate to discuss in detail here. The distinction between categories and channels is important.

A channel is an output specification. The null channel, for example, dismisses any output sent to the channel.

A category is a type of data. The category security is one of many categories. To log messages of type (category) security, for example, to the default_syslog channel, use the following:

    logging {
        category security { default_syslog; };
        // ...
    };

To turn off logging for certain types of data, send it to the null channel, as is done in the example named.conf shown earlier:

    logging {
            category lame-servers { null; };
            category cname { null; };
    };

This means that messages of types lame-servers and cname are being discarded.

There are reasonable defaults for logging. This means that a named.conf without logging statement is possible.

A zone defined in named.conf will be available as @ inside the corresponding zone file. The @ is called the current origin. For example,

    zone "127.in-addr.arpa" {
            type master;
            file "/etc/bind/db.127";
    };

will result in a current origin of 127.in-addr.arpa that is available as @ in file etc/bind/db.127.

Details about zone files, as well as how to create your own zone files and statements will be covered in the section called “Create And Maintain DNS Zones (2.207.2)”.