ddns-confgen8

Usage

Overview

tsig-keygen and ddns-confgen are invocation methods for a utility that generates keys for use in TSIG signing. The resulting keys can be used, for example, to secure dynamic DNS updates to a zone or for the rndc command channel.

When run as tsig-keygen, a domain name can be specified on the command line which will be used as the name of the generated key. If no name is specified, the default is tsig-key.

When run as ddns-confgen, the generated key is accompanied by configuration text and instructions that can be used with nsupdate and named when setting up dynamic DNS, including an example update-policy statement. (This usage similar to the rndc-confgen command for setting up command channel security.)

Note that named itself can configure a local DDNS key for use with nsupdate -l: it does this when a zone is configured with update-policy local;. ddns-confgen is only needed when a more elaborate configuration is required: for instance, if nsupdate is to be used from a remote system.

Options

-a algorithm

Specifies the algorithm to use for the TSIG key. Available choices are: hmac-md5, hmac-sha1, hmac-sha224, hmac-sha256, hmac-sha384 and hmac-sha512. The default is hmac-sha256. Options are case-insensitive, and the "hmac-" prefix may be omitted.

-h

Prints a short summary of options and arguments.

-k keyname

Specifies the key name of the DDNS authentication key. The default is ddns-key when neither the -s nor -z option is specified; otherwise, the default is ddns-key as a separate label followed by the argument of the option, e.g., ddns-key.example.com. The key name must have the format of a valid domain name, consisting of letters, digits, hyphens and periods.

-q

(ddns-confgen only.) Quiet mode: Print only the key, with no explanatory text or usage examples; This is essentially identical to tsig-keygen.

-r randomfile

Specifies a source of random data for generating the authorization. If the operating system does not provide a /dev/random or equivalent device, the default source of randomness is keyboard input. randomdev specifies the name of a character device or file containing random data to be used instead of the default. The special value keyboard indicates that keyboard input should be used.

-s name

(ddns-confgen only.) Generate configuration example to allow dynamic updates of a single hostname. The example named.conf text shows how to set an update policy for the specified name using the "name" nametype. The default key name is ddns-key.name. Note that the "self" nametype cannot be used, since the name to be updated may differ from the key name. This option cannot be used with the -z option.

-z zone

(ddns-confgen only.) Generate configuration example to allow dynamic updates of a zone: The example named.conf text shows how to set an update policy for the specified zone using the "zonesub" nametype, allowing updates to all subdomain names within that zone. This option cannot be used with the -s option.