Net::DNS man page on Kali

Man page or keyword search:  
man Server   9211 pages
apropos Keyword Search (all sections)
Output format
Kali logo
[printable version]

Net::DNS(3pm)	      User Contributed Perl Documentation	 Net::DNS(3pm)

NAME
       Net::DNS - Perl Interface to the Domain Name System

SYNOPSIS
	   use Net::DNS;

DESCRIPTION
       Net::DNS is a collection of Perl modules that act as a Domain Name
       System (DNS) resolver. It allows the programmer to perform DNS queries
       that are beyond the capabilities of "gethostbyname" and
       "gethostbyaddr".

       The programmer should be somewhat familiar with the format of a DNS
       packet and its various sections. See RFC 1035 or DNS and BIND (Albitz &
       Liu) for details.

   Resolver Objects
       A resolver object is an instance of the Net::DNS::Resolver class.  A
       program can have multiple resolver objects, each maintaining its own
       state information such as the nameservers to be queried, whether
       recursion is desired, etc.

   Packet Objects
       Net::DNS::Resolver queries return Net::DNS::Packet objects.  Packet
       objects have five sections:

       ·  The header section, a Net::DNS::Header object.

       ·  The question section, a list of Net::DNS::Question objects.

       ·  The answer section, a list of Net::DNS::RR objects.

       ·  The authority section, a list of Net::DNS::RR objects.

       ·  The additional section, a list of Net::DNS::RR objects.

   Update Objects
       Net::DNS::Update is a subclass of Net::DNS::Packet used to create
       dynamic update requests.

   Header Objects
       Net::DNS::Header objects represent the header section of a DNS packet.

   Question Objects
       Net::DNS::Question objects represent the content of the question
       section of a DNS packet.

   RR Objects
       Net::DNS::RR is the base class for DNS resource record (RR) objects in
       the answer, authority, and additional sections of a DNS packet.

       Do not assume that RR objects will be of the type requested.  The type
       of an RR object must be checked before calling any methods.

METHODS
       See the manual pages listed above for other class-specific methods.

   version
	   print Net::DNS->version, "\n";

       Returns the version of Net::DNS.

   rr
	   # Use a default resolver -- can not get an error string this way.
	   use Net::DNS;
	   my @rr = rr("example.com");
	   my @rr = rr("example.com", "A");
	   my @rr = rr("example.com", "A", "IN");

	   # Use your own resolver object.
	   my $res = Net::DNS::Resolver->new;
	   my @rr  = rr($res, "example.com" ... );

	   my ($ptr) = rr("192.0.2.1");

       The rr() method provides simple RR lookup for scenarios where the full
       flexibility of Net::DNS is not required.

       Returns a list of Net::DNS::RR objects for the specified name or an
       empty list if the query failed or no record was found.

       See "EXAMPLES" for more complete examples.

   mx
	   # Use a default resolver -- can not get an error string this way.
	   use Net::DNS;
	   my @mx = mx("example.com");

	   # Use your own resolver object.
	   my $res = Net::DNS::Resolver->new;
	   my @mx  = mx($res, "example.com");

       Returns a list of Net::DNS::RR::MX objects representing the MX records
       for the specified name.	The list will be sorted by preference.
       Returns an empty list if the query failed or no MX record was found.

       This method does not look up A records; it only performs MX queries.

Dynamic DNS Update Support
       The Net::DNS module provides auxiliary functions which support dynamic
       DNS update requests.

   yxrrset
       Use this method to add an "RRset exists" prerequisite to a dynamic
       update packet.  There are two forms, value-independent and value-
       dependent:

	   # RRset exists (value-independent)
	   $update->push(pre => yxrrset("host.example.com A"));

       Meaning:	 At least one RR with the specified name and type must exist.

	   # RRset exists (value-dependent)
	   $update->push(pre => yxrrset("host.example.com A 10.1.2.3"));

       Meaning:	 At least one RR with the specified name and type must exist
       and must have matching data.

       Returns a Net::DNS::RR object or "undef" if the object could not be
       created.

   nxrrset
       Use this method to add an "RRset does not exist" prerequisite to a
       dynamic update packet.

	   $update->push(pre => nxrrset("host.example.com A"));

       Meaning:	 No RRs with the specified name and type can exist.

       Returns a Net::DNS::RR object or "undef" if the object could not be
       created.

   yxdomain
       Use this method to add a "name is in use" prerequisite to a dynamic
       update packet.

	   $update->push(pre => yxdomain("host.example.com"));

       Meaning:	 At least one RR with the specified name must exist.

       Returns a Net::DNS::RR object or "undef" if the object could not be
       created.

   nxdomain
       Use this method to add a "name is not in use" prerequisite to a dynamic
       update packet.

	   $update->push(pre => nxdomain("host.example.com"));

       Meaning:	 No RR with the specified name can exist.

       Returns a Net::DNS::RR object or "undef" if the object could not be
       created.

   rr_add
       Use this method to add RRs to a zone.

	   $update->push(update => rr_add("host.example.com A 10.1.2.3"));

       Meaning:	 Add this RR to the zone.

       RR objects created by this method should be added to the "update"
       section of a dynamic update packet.  The TTL defaults to 86400 seconds
       (24 hours) if not specified.

       Returns a Net::DNS::RR object or "undef" if the object could not be
       created.

   rr_del
       Use this method to delete RRs from a zone.  There are three forms:
       delete all RRsets, delete an RRset, and delete a specific RR.

	   # Delete all RRsets.
	   $update->push(update => rr_del("host.example.com"));

       Meaning:	 Delete all RRs having the specified name.

	   # Delete an RRset.
	   $update->push(update => rr_del("host.example.com A"));

       Meaning:	 Delete all RRs having the specified name and type.

	   # Delete a specific RR.
	   $update->push(update => rr_del("host.example.com A 10.1.2.3"));

       Meaning:	 Delete all RRs having the specified name, type, and data.

       RR objects created by this method should be added to the "update"
       section of a dynamic update packet.

       Returns a Net::DNS::RR object or "undef" if the object could not be
       created.

Zone Serial Number Management
       The Net::DNS module provides auxiliary functions which support policy-
       driven zone serial numbering regimes.

   SEQUENTIAL
	   $successor = $soa->serial( SEQUENTIAL );

       The existing serial number is incremented modulo 2**32.

   UNIXTIME
	   $successor = $soa->serial( UNIXTIME );

       The Unix time scale will be used as the basis for zone serial
       numbering. The serial number will be incremented if the time elapsed
       since the previous update is less than one second.

   YYYYMMDDxx
	   $successor = $soa->serial( YYYYMMDDxx );

       The 32 bit value returned by the auxiliary YYYYMMDDxx() function will
       be used as the base for the date-coded zone serial number.  Serial
       number increments must be limited to 100 per day for the date
       information to remain useful.

Sorting of RR arrays
       rrsort() provides functionality to help you sort RR arrays. In most
       cases rrsort() will give you the answer that you want, but you can
       specify your own sorting method by using the
       "Net::DNS::RR::FOO->set_rrsort_func()" class method. See Net::DNS::RR
       for details.

   rrsort()
	   use Net::DNS;

	   my @sorted = rrsort( $rrtype, $attribute, @rr_array );

       rrsort() selects all RRs from the input array that are of the type
       defined by the first argument. Those RRs are sorted based on the
       attribute that is specified as second argument.

       There are a number of RRs for which the sorting function is defined in
       the code.

       For instance:

	   my @prioritysorted = rrsort( "SRV", "priority", @rr_array );

       returns the SRV records sorted from lowest to highest priority and for
       equal priorities from highest to lowest weight.

       If the function does not exist then a numerical sort on the attribute
       value is performed.

	   my @portsorted = rrsort( "SRV", "port", @rr_array );

       If the attribute is not defined then either the default_sort() function
       or "canonical sorting" (as defined by DNSSEC) will be used.

       rrsort() returns a sorted array containing only elements of the
       specified RR type.  Any other RR types are silently discarded.

       rrsort() returns an empty list when arguments are incorrect.

EXAMPLES
       The following brief examples illustrate some of the features of
       Net::DNS.  The documentation for individual modules and the demo
       scripts included with the distribution provide more extensive examples.

       See Net::DNS::Update for an example of performing dynamic updates.

   Look up host addresses.
	   use Net::DNS;
	   my $res   = Net::DNS::Resolver->new;
	   my $reply = $res->search("host.example.com");

	   if ($reply) {
	       foreach my $rr ($reply->answer) {
		   print $rr->address, "\n" if $rr->type eq "A";
	       }
	   } else {
	       warn "query failed: ", $res->errorstring, "\n";
	   }

   Find the nameservers for a domain.
	   use Net::DNS;
	   my $res   = Net::DNS::Resolver->new;
	   my $reply = $res->query("example.com", "NS");

	   if ($reply) {
	       foreach $rr (grep { $_->type eq 'NS' } $reply->answer) {
		   print $rr->nsdname, "\n";
	       }
	   } else {
	       warn "query failed: ", $res->errorstring, "\n";
	   }

   Find the MX records for a domain.
	   use Net::DNS;
	   my $name = "example.com";
	   my $res  = Net::DNS::Resolver->new;
	   my @mx   = mx($res, $name);

	   if (@mx) {
	       foreach $rr (@mx) {
		   print $rr->preference, " ", $rr->exchange, "\n";
	       }
	   } else {
	       warn "Can not find MX records for $name: ", $res->errorstring, "\n";
	   }

   Print domain SOA record in zone file format.
	   use Net::DNS;
	   my $res   = Net::DNS::Resolver->new;
	   my $reply = $res->query("example.com", "SOA");

	   if ($reply) {
	       ($reply->answer)[0]->print;
	   } else {
	       print "query failed: ", $res->errorstring, "\n";
	   }

   Perform a zone transfer and print all the records.
	   use Net::DNS;
	   my $res  = Net::DNS::Resolver->new;
	   $res->nameservers("ns.example.com");

	   my @zone = $res->axfr("example.com");

	   foreach $rr (@zone) {
	       $rr->print;
	   }

   Perform a background query and print the reply.
	   use Net::DNS;
	   my $res    = Net::DNS::Resolver->new;
	   my $socket = $res->bgsend("host.example.com");

	   while ( $res->bgbusy($socket) ) {
	       # do some work here while waiting for the answer
	       # ...and some more here
	   }

	   my $packet = $res->bgread($socket);
	   $packet->print;

BUGS
       Net::DNS is slow.

       For other items to be fixed, or if you discover a bug in this
       distribution please use the CPAN bug reporting system.

COPYRIGHT
       Copyright (c)1997-2000 Michael Fuhr.

       Portions Copyright (c)2002,2003 Chris Reinhardt.

       Portions Copyright (c)2005 Olaf Kolkman (RIPE NCC)

       Portions Copyright (c)2006 Olaf Kolkman (NLnet Labs)

       Portions Copyright (c)2014 Dick Franks

       All rights reserved.

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.

AUTHOR INFORMATION
       Net::DNS is maintained at NLnet Labs (www.nlnetlabs.nl) by Willem
       Toorop.

       Between 2005 and 2012 Net::DNS was maintained by Olaf Kolkman.

       Between 2002 and 2004 Net::DNS was maintained by Chris Reinhardt.

       Net::DNS was created in 1997 by Michael Fuhr.

SEE ALSO
       perl, Net::DNS::Resolver, Net::DNS::Question, Net::DNS::RR,
       Net::DNS::Packet, Net::DNS::Update, RFC1035, <http://www.net-dns.org/>,
       DNS and BIND by Paul Albitz & Cricket Liu

perl v5.26.0			  2017-07-31			 Net::DNS(3pm)
[top]

List of man pages available for Kali

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net