Net::DNS::Update(3) User Contributed Perl Documentation Net::DNS::Update(3)NAMENet::DNS::Update - Create a DNS update packet
SYNOPSIS
use Net::DNS;
$update = new Net::DNS::Update( 'example.com', 'IN' );
$update->push( prereq => nxrrset('foo.example.com. A') );
$update->push( update => rr_add('foo.example.com. 86400 A 192.168.1.2') );
DESCRIPTIONNet::DNS::Update is a subclass of Net::DNS::Packet, to be used for
making DNS dynamic updates.
Programmers should refer to RFC2136 for dynamic update semantics.
WARNING: This code is still under development. Please use with
caution on production nameservers.
METHODS
new
$update = new Net::DNS::Update;
$update = new Net::DNS::Update( 'example.com' );
$update = new Net::DNS::Update( 'example.com', 'HS' );
Returns a Net::DNS::Update object suitable for performing a DNS dynamic
update. Specifically, it creates a packet with the header opcode
set to UPDATE and the zone record type to SOA (per RFC 2136, Section
2.3).
Programs must use the push() method to add RRs to the prerequisite,
update, and additional sections before performing the update.
Arguments are the zone name and the class. If the zone is omitted, the
default domain will be taken from the resolver configuration. If the
class is omitted, it defaults to IN.
EXAMPLES
The first example below shows a complete program; subsequent examples
show only the creation of the update packet .
Add a new host
#!/usr/bin/perl
use Net::DNS;
# Create the update packet.
my $update = new Net::DNS::Update('example.com');
# Prerequisite is that no A records exist for the name.
$update->push( pre => nxrrset('foo.example.com. A') );
# Add two A records for the name.
$update->push( update => rr_add('foo.example.com. 86400 A 192.168.1.2') );
$update->push( update => rr_add('foo.example.com. 86400 A 172.16.3.4') );
# Send the update to the zone's primary master.
my $resolver = new Net::DNS::Resolver;
$resolver->nameservers('primary-master.example.com');
my $reply = $resolver->send($update);
# Did it work?
if ($reply) {
if ( $reply->header->rcode eq 'NOERROR' ) {
print "Update succeeded\n";
} else {
print 'Update failed: ', $reply->header->rcode, "\n";
}
} else {
print 'Update failed: ', $resolver->errorstring, "\n";
}
Add an MX record for a name that already exists
my $update = new Net::DNS::Update('example.com');
$update->push( prereq => yxdomain('example.com') );
$update->push( update => rr_add('example.com MX 10 mailhost.example.com') );
Add a TXT record for a name that doesn't exist
my $update = new Net::DNS::Update('example.com');
$update->push( prereq => nxdomain('info.example.com') );
$update->push( update => rr_add('info.example.com TXT "yabba dabba doo"') );
Delete all A records for a name
my $update = new Net::DNS::Update('example.com');
$update->push( prereq => yxrrset('foo.example.com A') );
$update->push( update => rr_del('foo.example.com A') );
Delete all RRs for a name
my $update = new Net::DNS::Update('example.com');
$update->push( prereq => yxdomain('byebye.example.com') );
$update->push( update => rr_del('byebye.example.com') );
Perform a DNS update signed using a BIND key file
my $update = new Net::DNS::Update('example.com');
$update->push( update => rr_add('foo.example.com A 10.1.2.3') );
$update->push( update => rr_add('bar.example.com A 10.4.5.6') );
$update->sign_tsig( "$dir/Khmac-sha512.example.com.+165+01018.private" );
The corresponding public key file may also be used:
$update->sign_tsig( "$dir/Khmac-sha512.example.com.+165+01018.key" );
Another way to perform a signed update
my $key_name = 'tsig-key';
my $key = 'awwLOtRfpGE+rRKF2+DEiw==';
my $update = new Net::DNS::Update('example.com');
$update->push( update => rr_add('foo.example.com A 10.1.2.3') );
$update->push( update => rr_add('bar.example.com A 10.4.5.6') );
$update->sign_tsig( $key_name, $key );
Perform a signed update with a customized TSIG record
my $key_name = 'tsig-key';
my $key = 'awwLOtRfpGE+rRKF2+DEiw==';
my $tsig = new Net::DNS::RR("$key_name TSIG $key");
$tsig->fudge(60);
my $update = new Net::DNS::Update('example.com');
$update->push( update => rr_add('foo.example.com A 10.1.2.3') );
$update->push( update => rr_add('bar.example.com A 10.4.5.6') );
$update->push( additional => $tsig );
BUGS
This code is still under development. Please use with caution on
production nameservers.
COPYRIGHT
Copyright (c) 1997-2002 Michael Fuhr.
Portions Copyright (c) 2002-2004 Chris Reinhardt.
All rights reserved. This program is free software; you may
redistribute it and/or modify it under the same terms as Perl itself.
SEE ALSO
perl, Net::DNS, Net::DNS::Packet, Net::DNS::Header, Net::DNS::RR,
Net::DNS::Resolver, RFC 2136, RFC 2845
perl v5.18.2 2014-01-16 Net::DNS::Update(3)
