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.
OPTIONS
-b 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.
-c config-file
Use
config-file
as the configuration file instead of the default,
/etc/namedb/rndc.conf.
-k key-file
Use
key-file
as the key file instead of the default,
/etc/namedb/rndc.key. The key in
/etc/namedb/rndc.key
will be used to authenticate commands sent to the server if the
config-file
does not exist.
-s server
server
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.
-p port
Send commands to TCP port
port
instead of BIND 9's default control channel port, 953.
-V
Enable verbose logging.
-y 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.
For the complete set of commands supported by
rndc, see the BIND 9 Administrator Reference Manual or run
rndc
without arguments to see its help message.
LIMITATIONS
rndc
does not yet support all the commands of the BIND 8
ndc
utility.
There is currently no way to provide the shared secret for a
key_id
without using the configuration file.