The named.conf File (System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP))

System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP)

The `named.conf` File

The BIND configuration file, /etc/named.conf establishes the server as a master, slave, or cache-only name server. It also specifies the zones over which the server has authority and which data files it should read to get its initial data.

The /etc/named.conf file contains statements that implement the following.

Security through an Access Control List (ACL) that defines a collection of IP addresses that an NIS+ host has read/write access
Logging specifications
Selectively applied options for a set of zones, rather than to all zones

The configuration file is read by in.named when the daemon is started by the server's start up script, /etc/init.d/inetsvc. The configuration file directs in.named either to other servers or to local data files for a specified domain.

`named.conf` Statements

The named.conf file contains statements and comments. Statements end with a semicolon. Some statements can contain a contain a block of statements. Again, each statement in the block is terminated with a semicolon.

The named.conf file supports the following statements.

Table 5–4 named.conf Statements


Statement	Description
`acl`	Defines a named IP address match list used for access control. The address match list designates one or more IP addresses (dotted-decimal notation) or IP prefixes (dotted-decimal notation followed with a slash and the number of bits in the netmask). The named IP address match list must be defined by an `acl` statement before it can be used elsewhere; no forward references allowed.
`include`	Inserts an include file at the point where the `include` statement is encountered. Use `include` to break up the configuration into more easily managed chunks.
`key`	Specifies a key ID used for authentication and authorization on a particular name server. See the `server` statement.
`logging`	Specifies the information the server logs and the destination of log messages.
`options`	Controls global server configuration options and sets default values for other statements.
`server`	Sets designated configuration options associated with a remote name server. Selectively applies options on a per-server basis, rather than to all servers.
`zone`	Defines a zone. Selectively applies options on a per-zone basis, rather than to all zones.

Example 5–13 Example Master Configuration File for a master server

options {
         directory "/var/named";
         datasize 2098;
         forward only;
         forwarders {
                  99.11.33.44;
         };
         recursion no;
         transfers-in 10;
         transfers-per-ns 2;
         allow-transfer {
                  127.0.1.1/24;
         };
};

logging {
         category queries { default_syslog; };
};

include "/var/named/abcZones.conf"

// here are the names of the master files
zone "cities.zn" {
         type master;
         file "db.cities.zn";
};

zone "0.0.127.in-addr.arpa." {
         type master;
         file "db.127.cities.zn";
};

zone "168.192.in-addr.arpa" {
         type master;
         file "db.cities.zn.rev";
};

zone "sales.doc.com" {
         type slave;
         file "slave/db.sales.doc";
         masters {
                  192.168.1.151;
         };
};

zone "168.192.in-addr.arpa" {
         type slave;
         file "slave/db.sales.doc.rev";
         masters {
                  192.168.1.151;
         };
};