Etc/Named.conf; Common Statement Types - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

Note
If you have installed the bind-chroot package, the BIND service will run in the /
var/named/chroot environment. All configuration files will be moved there. As such,
named.conf will be located in /var/named/chroot/etc/named.conf, and so on.
Tip
If you have installed the caching-nameserver package, the default configuration file is
/etc/named.caching-nameserver.conf. To override this default configuration, you
can create your own custom configuration file in /etc/named.conf. BIND will use the /
etc/named.conf custom file instead of the default configuration file after you restart.
The next few sections review the BIND configuration files in more detail.

17.2. /etc/named.conf

The named.conf file is a collection of statements using nested options surrounded by opening and
closing ellipse characters, { }. Administrators must be careful when editing named.conf to avoid
syntax errors as many seemingly minor errors prevent the named service from starting.
A typical named.conf file is organized similar to the following example:
<statement-1> ["<statement-1-name>"] [<statement-1-class>] { <option-1>; <option-2>; <option-
N>; }; <statement-2> ["<statement-2-name>"] [<statement-2-class>]
{ <option-1>; <option-2>; <option-N>; }; <statement-N> ["<statement-N-name>"] [<statement-N-
class>] { <option-1>; <option-2>; <option-N>; };

17.2.1. Common Statement Types

The following types of statements are commonly used in /etc/named.conf:
17.2.1.1. acl Statement
The acl statement (or access control statement) defines groups of hosts which can then be permitted
or denied access to the nameserver.
An acl statement takes the following form:
acl <acl-name> { <match-element>; [<match-element>; ...] };
In this statement, replace <acl-name> with the name of the access control list and replace <match-
element> with a semi-colon separated list of IP addresses. Most of the time, an individual IP address
or IP network notation (such as 10.0.1.0/24) is used to identify the IP addresses within the acl
statement.
The following access control lists are already defined as keywords to simplify configuration:
• any — Matches every IP address
/etc/named.conf
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