Net::DNS::Resolver::Recurse

Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME

Net::DNS::Resolver::Recurse - DNS recursive resolver

SYNOPSIS

    use Net::DNS::Resolver::Recurse;

    my $resolver = new Net::DNS::Resolver::Recurse();
    $resolver->debug(1);

    $resolver->hints('198.41.0.4');     # A.ROOT-SERVER.NET.

    my $packet = $resolver->send( 'www.rob.com.au.', 'A' );

DESCRIPTION

This module is a subclass of Net::DNS::Resolver.

METHODS

This module inherits almost all the methods from Net::DNS::Resolver. Additional module-specific methods are described below.

hints

This method specifies a list of the IP addresses of nameservers to be used to discover the addresses of the root nameservers.

    $resolver->hints(@ip);

If no hints are passed, the priming query is directed to nameservers drawn from a built-in list of IP addresses.

query, search, send

The query(), search() and send() methods produce the same result as their counterparts in Net::DNS::Resolver.

    $packet = $resolver->send( 'www.example.com.', 'A' );

Server-side recursion is suppressed by clearing the recurse flag in query packets and recursive name resolution is performed explicitly.

The query() and search() methods are inherited from Net::DNS::Resolver and invoke send() indirectly.

callback

This method specifies a code reference to a subroutine, which is then invoked at each stage of the recursive lookup.

For example to emulate dig's "+trace" function:

    my $coderef = sub {
        my $packet = shift;

        printf ";; Received %d bytes from %s\n\n",
                $packet->answersize, $packet->answerfrom;
    };

    $resolver->callback($coderef);

The callback subroutine is not called for queries for missing glue records.

ACKNOWLEDGEMENT

This package is an improved and compatible reimplementation of the Net::DNS::Resolver::Recurse.pm created by Rob Brown in 2002, whose contribution is gratefully acknowledged.

COPYRIGHT

LICENSE

Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of the author not be used in advertising or publicity pertaining to distribution of the software without specific prior written permission.

THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.