rndc — name server control utility
rndc  [-b ] [source-address-c ] [config-file-k ] [key-file-s ] [server-p ] [port-V] [-y ] {command}key_id
rndc controls the operation of a name server. It supersedes the ndc utility that was provided in old BIND releases. If rndc is invoked with no command line options or arguments, it prints a short summary of the supported commands and the available options and their arguments.
rndc communicates with the name server over a TCP connection, sending commands authenticated with digital signatures. In the current versions of rndc and named, the only supported authentication algorithm is HMAC-MD5, which uses a shared secret on each end of the connection. This provides TSIG-style authentication for the command request and the name server's response. All commands sent over the channel must be signed by a key_id known to the server.
rndc reads a configuration file to determine how to contact the name server and decide what algorithm and key it should use.
source-address
            Use source-address
            as the source address for the connection to the server.
            Multiple instances are permitted to allow setting of both
            the IPv4 and IPv6 source addresses.
          
config-file
            Use config-file
            as the configuration file instead of the default,
            /etc/rndc.conf.
          
key-file
            Use key-file
            as the key file instead of the default,
            /etc/rndc.key.  The key in
            /etc/rndc.key will be used to
            authenticate
            commands sent to the server if the config-file
            does not exist.
          
serverserver is
            the name or address of the server which matches a
            server statement in the configuration file for
            rndc.  If no server is supplied on the
            command line, the host named by the default-server clause
            in the options statement of the rndc
	    configuration file will be used.
          
port
            Send commands to TCP port
            port
            instead
            of BIND 9's default control channel port, 953.
          
Enable verbose logging.
key_id
            Use the key key_id
            from the configuration file.
            key_id
            must be
            known by named with the same algorithm and secret string
            in order for control message validation to succeed.
            If no key_id
            is specified, rndc will first look
            for a key clause in the server statement of the server
            being used, or if no server statement is present for that
            host, then the default-key clause of the options statement.
            Note that the configuration file contains shared secrets
            which are used to send authenticated control commands
            to name servers.  It should therefore not have general read
            or write access.
          
A list of commands supported by rndc can be seen by running rndc without arguments.
Currently supported commands are:
reloadReload configuration file and zones.
reload zone [class [view]]Reload the given zone.
refresh zone [class [view]]Schedule zone maintenance for the given zone.
retransfer zone [class [view]]Retransfer the given zone from the master.
freeze [zone [class [view]]]Suspend updates to a dynamic zone. If no zone is specified, then all zones are suspended. This allows manual edits to be made to a zone normally updated by dynamic update. It also causes changes in the journal file to be synced into the master file, and the journal file to be removed. All dynamic update attempts will be refused while the zone is frozen.
thaw [zone [class [view]]]Enable updates to a frozen dynamic zone. If no zone is specified, then all frozen zones are enabled. This causes the server to reload the zone from disk, and re-enables dynamic updates after the load has completed. After a zone is thawed, dynamic updates will no longer be refused.
notify zone [class [view]]Resend NOTIFY messages for the zone.
reconfigReload the configuration file and load new zones, but do not reload existing zone files even if they have changed. This is faster than a full reload when there is a large number of zones because it avoids the need to examine the modification times of the zones files.
statsWrite server statistics to the statistics file.
querylog [on|off] 
            Toggle query logging.  Query logging can also be enabled
            by explicitly directing the queries
            category to a
            channel in the
            logging section of
            named.conf or by specifying
            querylog yes; in the
            options section of
            named.conf.
          
dumpdb [-all|-cache|-zone] [view ...]Dump the server's caches (default) and/or zones to the dump file for the specified views. If no view is specified, all views are dumped.
stop [-p]
            Stop the server, making sure any recent changes
            made through dynamic update or IXFR are first saved to
            the master files of the updated zones.
            If -p is specified named's process id is returned.
            This allows an external process to determine when named
            had completed stopping.
          
halt [-p]
            Stop the server immediately.  Recent changes
            made through dynamic update or IXFR are not saved to
            the master files, but will be rolled forward from the
            journal files when the server is restarted.
            If -p is specified named's process id is returned.
            This allows an external process to determine when named
            had completed halting.
          
traceIncrement the servers debugging level by one.
trace levelSets the server's debugging level to an explicit value.
notraceSets the server's debugging level to 0.
flushFlushes the server's cache.
flushname name [view] Flushes the given name from the server's cache.
statusDisplay status of the server. Note that the number of zones includes the internal bind/CH zone and the default ./IN hint zone if there is not an explicit root zone configured.
recursingDump the list of queries named is currently recursing on.
validation ( on | off | check ) [view ...] 
            Enable, disable, or check the current status of
            DNSSEC validation.
            Note dnssec-enable also needs to be
            set to yes or
            auto to be effective.
            It defaults to enabled.
          
tsig-listList the names of all TSIG keys currently configured for use by named in each view. The list both statically configured keys and dynamic TKEY-negotiated keys.
tsig-delete keyname [view]Delete a given TKEY-negotiated key from the server. (This does not apply to statically configured TSIG keys.)
      There is currently no way to provide the shared secret for a
      key_id without using the configuration file.
    
Several error messages could be clearer.