net::dns::faq(1) [redhat man page]

FAQ(1)							User Contributed Perl Documentation						    FAQ(1)

SYNOPSIS

	perldoc Net::DNS::FAQ

DESCRIPTION

       This document serves to answer the most frequently asked questions on both the Net::DNS Mailing List and those sent to the author.

       The latest version of this FAQ can be found at	   http://www.net-dns.org/docs/FAQ.html

GENERAL

       What is Net::DNS?

       Net::DNS is a pure perl implementation of a DNS resolver.

INSTALLATION

       Where can I find Test::More?

       Test::More is part of the Test-Simple packge, by Michael G Schwern.  You should be able to find the distrubution here:

	       http://search.cpan.org/author/MSCHWERN/

GENERAL QUESTIONS

       Why does Net::DNS::Resolver::query() return undef when the ANSWER section is empty?

       The short answer is, don't use query().	Net::DNS::Resolver::send() will always return the answer packet, as long as an answer was
       received.

       The longer answer is that query() is modeled after the res_query() function from the libresolv C library, which has similar behaviors.

perl v5.8.0							    2002-11-15								    FAQ(1)

Net::DNS::Resolver::Recurse(3)				User Contributed Perl Documentation			    Net::DNS::Resolver::Recurse(3)

NAME

       Net::DNS::Resolver::Recurse - Perform recursive dns lookups

SYNOPSIS

	 use Net::DNS::Resolver::Recurse;
	 my $res = Net::DNS::Resolver::Recurse->new;

DESCRIPTION

       This module is a sub class of Net::DNS::Resolver. So the methods for Net::DNS::Resolver still work for this module as well.  There are just
       a couple methods added:

   hints
       Initialize the hint servers.  Recursive queries need a starting name server to work off of. This method takes a list of IP addresses to use
       as the starting servers.  These name servers should be authoritative for the root (.) zone.

	 $res->hints(@ips);

       If no hints are passed, the default nameserver is asked for the hints.  Normally these IPs can be obtained from the following location:

	 ftp://ftp.internic.net/domain/named.root

   recursion_callback
       This method is takes a code reference, which is then invoked each time a packet is received during the recursive lookup.  For example to
       emulate dig's "+trace" function:

	$res->recursion_callback(sub {
	    my $packet = shift;

	    $_->print for $packet->additional;

	    printf(";; Received %d bytes from %s

",
		$packet->answersize,
		$packet->answerfrom
	    );
	});

   query_dorecursion
       This method is much like the normal query() method except it disables the recurse flag in the packet and explicitly performs the recursion.

	 $packet = $res->query_dorecursion( "www.netscape.com.", "A");

IPv6 transport
       If the appropriate IPv6 libraries are installed the recursive resolver will randomly choose between IPv6 and IPv4 addresses of the
       nameservers it encounters during recursion.

       If you want to force IPv4 transport use the force_v4() method. Also see the IPv6 transport notes in the Net::DNS::Resolver documentation.

AUTHOR

       Rob Brown, bbb@cpan.org

SEE ALSO

       Net::DNS::Resolver,

COPYRIGHT

       Copyright (c) 2002, Rob Brown.  All rights reserved.  Portions Copyright (c) 2005, Olaf M Kolkman.

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

       $Id: Recurse.pm 1096 2012-12-28 13:35:15Z willem $

perl v5.18.2							    2014-01-16					    Net::DNS::Resolver::Recurse(3)