17.2.3. Using the rndc Utility The rndc utility is a command-line tool that allows you to administer the named service, both locally and from a remote machine. Its usage is as follows: 17.2.3.1. Configuring the Utility To prevent unauthorized access to the service, named must be configured to listen on the selected port (that is, 953 by default), and an identical key must be used by both the service and the rndc utility. Table 17.7. Relevant files Path Description /etc/named.conf The default configuration file for the named service. /etc/rndc.conf The default configuration file for the rndc utility. /etc/rndc.key The default key location. The rndc configuration is located in /etc/rndc.conf . If the file does not exist, the utility will use the key located in /etc/rndc.key , which was generated automatically during the installation process using the rndc-confgen -a command. The named service is configured using the controls statement in the /etc/named.conf configuration file as described in Section 17.2.1.2, "Other Statement Types" . Unless this statement is present, only the connections from the loopback address (that is, 127.0.0.1 ) will be allowed, and the key located in /etc/rndc.key will be used. For more information on this topic, see manual pages and the BIND 9 Administrator Reference Manual listed in Section 17.2.7, "Additional Resources" . Important To prevent unprivileged users from sending control commands to the service, make sure only root is allowed to read the /etc/rndc.key file: 17.2.3.2. Checking the Service Status To check the current status of the named service, use the following command: 17.2.3.3. Reloading the Configuration and Zones To reload both the configuration file and zones, type the following at a shell prompt: This will reload the zones while keeping all previously cached responses, so that you can make changes to the zone files without losing all stored name resolutions. To reload a single zone, specify its name after the reload command, for example: Finally, to reload the configuration file and newly added zones only, type: Note If you intend to manually modify a zone that uses Dynamic DNS (DDNS), make sure you run the freeze command first: Once you are finished, run the thaw command to allow the DDNS again and reload the zone: 17.2.3.4. Updating Zone Keys To update the DNSSEC keys and sign the zone, use the sign command. For example: Note that to sign a zone with the above command, the auto-dnssec option has to be set to maintain in the zone statement. For instance: 17.2.3.5. Enabling the DNSSEC Validation To enable the DNSSEC validation, type the following at a shell prompt: Similarly, to disable this option, type: See the options statement described in Section 17.2.1.1, "Common Statement Types" for information on how to configure this option in /etc/named.conf . 17.2.3.6. Enabling the Query Logging To enable (or disable in case it is currently enabled) the query logging, run the following command: To check the current setting, use the status command as described in Section 17.2.3.2, "Checking the Service Status" .

Commands:
rndc [ option ...] command [ command-option ]
~]# chmod o-rwx /etc/rndc.key
~]# rndc status version: 9.7.0-P2-RedHat-9.7.0-5.P2.el6 CPUs found: 1 worker threads: 1 number of zones: 16 debug level: 0 xfers running: 0 xfers deferred: 0 soa queries in progress: 0 query logging is OFF recursive clients: 0/0/1000 tcp clients: 0/100 server is up and running
~]# rndc reload server reload successful
~]# rndc reload localhost zone reload up-to-date
~]# rndc reconfig
~]# rndc freeze localhost
~]# rndc thaw localhost The zone reload and thaw was successful.
~]# rndc sign localhost
zone "localhost" IN { type master; file "named.localhost"; allow-update { none; }; auto-dnssec maintain; };
~]# rndc validation on
~]# rndc validation off
~]# rndc querylog