The Mac OS X
whois binary has a lot of options built in, including the
-h option which allows you to specify any host you want as a whois server.
The whois utility looks up records in the databases maintained by several Network Information Centers (NICs).
The options are as follows:
-6 Use the IPv6 Resource Center (6bone) database. It contains network names and addresses for the IPv6 net-
-A Use the Asia/Pacific Network Information Center (APNIC) database. It contains network numbers used in
East Asia, Australia, New Zealand, and the Pacific islands.
-a Use the American Registry for Internet Numbers (ARIN) database. It contains network numbers used in
those parts of the world covered neither by APNIC nor by RIPE.
(Hint: All point of contact handles in the ARIN whois database end with "-ARIN".)
-b Use the Network Abuse Clearinghouse database. It contains addresses to which network abuse should be
reported, indexed by domain name.
This is the equivalent of using the -h option with an argument of "country-code.whois-servers.net".
-d Use the US Department of Defense database. It contains points of contact for subdomains of .MIL.
-g Use the US non-military federal government database, which contains points of contact for subdomains of
Use the specified host instead of the default variant. Either a host name or an IP address may be speci-
All you need to know is which option corresponds to the whois server you want to search.
If you want to actually add a search option to whois that points to a new server, you'd need the source code so you can recompile it. If you run
strings /usr/bin/whois, you'll notice that the servers related to the options listed above are actually hard coded into the binary.