2013-03-14 ISC Internet Systems Consortium, Inc. rndc.conf 5 BIND9 rndc.conf rndc configuration file 2000 2001 2004 2005 2007 2013 2014 2015 2016 2018 2019 Internet Systems Consortium, Inc. ("ISC") rndc.conf DESCRIPTION rndc.conf is the configuration file for rndc, the BIND 9 name server control utility. This file has a similar structure and syntax to named.conf. Statements are enclosed in braces and terminated with a semi-colon. Clauses in the statements are also semi-colon terminated. The usual comment styles are supported: C style: /* */ C++ style: // to end of line Unix style: # to end of line rndc.conf is much simpler than named.conf. The file uses three statements: an options statement, a server statement and a key statement. The statement contains five clauses. The clause is followed by the name or address of a name server. This host will be used when no name server is given as an argument to rndc. The clause is followed by the name of a key which is identified by a statement. If no is provided on the rndc command line, and no clause is found in a matching statement, this default key will be used to authenticate the server's commands and responses. The clause is followed by the port to connect to on the remote name server. If no option is provided on the rndc command line, and no clause is found in a matching statement, this default port will be used to connect. The and clauses which can be used to set the IPv4 and IPv6 source addresses respectively. After the keyword, the server statement includes a string which is the hostname or address for a name server. The statement has three possible clauses: , and . The key name must match the name of a key statement in the file. The port number specifies the port to connect to. If an clause is supplied these addresses will be used instead of the server name. Each address can take an optional port. If an or of supplied then these will be used to specify the IPv4 and IPv6 source addresses respectively. The statement begins with an identifying string, the name of the key. The statement has two clauses. identifies the authentication algorithm for rndc to use; currently only HMAC-MD5 (for compatibility), HMAC-SHA1, HMAC-SHA224, HMAC-SHA256 (default), HMAC-SHA384 and HMAC-SHA512 are supported. This is followed by a secret clause which contains the base-64 encoding of the algorithm's authentication key. The base-64 string is enclosed in double quotes. There are two common ways to generate the base-64 string for the secret. The BIND 9 program rndc-confgen can be used to generate a random key, or the mmencode program, also known as mimencode, can be used to generate a base-64 string from known input. mmencode does not ship with BIND 9 but is available on many systems. See the EXAMPLE section for sample command lines for each. EXAMPLE options { default-server localhost; default-key samplekey; }; server localhost { key samplekey; }; server testserver { key testkey; addresses { localhost port 5353; }; }; key samplekey { algorithm hmac-sha256; secret "6FMfj43Osz4lyb24OIe2iGEz9lf1llJO+lz"; }; key testkey { algorithm hmac-sha256; secret "R3HI8P6BKw9ZwXwN3VZKuQ=="; }; In the above example, rndc will by default use the server at localhost (127.0.0.1) and the key called samplekey. Commands to the localhost server will use the samplekey key, which must also be defined in the server's configuration file with the same name and secret. The key statement indicates that samplekey uses the HMAC-SHA256 algorithm and its secret clause contains the base-64 encoding of the HMAC-SHA256 secret enclosed in double quotes. If rndc -s testserver is used then rndc will connect to server on localhost port 5353 using the key testkey. To generate a random secret with rndc-confgen: rndc-confgen A complete rndc.conf file, including the randomly generated key, will be written to the standard output. Commented-out and statements for named.conf are also printed. To generate a base-64 secret with mmencode: echo "known plaintext for a secret" | mmencode NAME SERVER CONFIGURATION The name server must be configured to accept rndc connections and to recognize the key specified in the rndc.conf file, using the controls statement in named.conf. See the sections on the statement in the BIND 9 Administrator Reference Manual for details. SEE ALSO rndc8 , rndc-confgen8 , mmencode1 , BIND 9 Administrator Reference Manual.