diff between "option domainname" and "ddns-domainname" ?

David W. Hankins David_Hankins at isc.org
Mon Jun 5 16:14:35 UTC 2006

On Sun, Jun 04, 2006 at 11:14:48PM -0800, kalyanasundaram S wrote:
> thanks simon,
> why the host declarations is being updated in dns while using ddns-domainname
> why not while using option domain-name

This is the default config, assuming interim style ddns updates:

char std_nsupdate [] = "                                                    \n\
option server.ddns-hostname =                                               \n\
  pick (option fqdn.hostname, option host-name);                            \n\
option server.ddns-domainname = config-option domain-name;                  \n\
option server.ddns-ttl = encode-int(lease-time / 2, 32);                    \n\
option server.ddns-rev-domainname = \"in-addr.arpa.\";";

'option' is derived from the cache of options supplied by the client.
'config-option' is derived from the server's cache of configuration
state (options it supplies to the client).

Seeing the default config in config language is probably a lot more
useful than what's currently codified in the manpages.  I'll make a
note to update that some day.

David W. Hankins		"If you don't do it right the first time,
Software Engineer			you'll just have to do it again."
Internet Systems Consortium, Inc.		-- Jack T. Hankins

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