NAME¶
Net::DNS::Update - DNS dynamic 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') );
DESCRIPTION¶
Net::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.
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') );
my $update = new Net::DNS::Update('example.com');
$update->push( update => rr_add('foo.example.com A 10.1.2.3') );
$update->sign_tsig( "$dir/Khmac-sha512.example.com.+165+01018.private" );
my $reply = $resolver->send( $update );
$reply->verify( $update ) || die $reply->verifyerr;
Signing the DNS update using a BIND public key file¶
$update->sign_tsig( "$dir/Khmac-sha512.example.com.+165+01018.key" );
Signing the DNS update using a customised TSIG record¶
$update->sign_tsig( "$dir/Khmac-sha512.example.com.+165+01018.private",
fudge => 60
);
Another way to sign a DNS update¶
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( additional => $tsig );
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