new¶

    $update = Net::DNS::Update->new;
    $update = Net::DNS::Update->new('example.com');
    $update = Net::DNS::Update->new('example.com', 'HS');

Returns a "Net::DNS::Update" object used to perform a DNS dynamic update operation. Specifically, it creates a packet with the header opcode set to UPDATE and zone qtype to SOA (per RFC 2136, 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.

Future versions of "Net::DNS" may provide a simpler interface for making dynamic updates.

Add a new host¶

    #!/usr/bin/perl -w
    use strict;
    use Net::DNS;
    # Create the update packet.
    my $update = Net::DNS::Update->new('example.com');
    # Prerequisite is that no A records exist for the name.
    $update->push(prerequisite => 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 $res = Net::DNS::Resolver->new;
    $res->nameservers('primary-master.example.com');
    my $reply = $res->send($update);
    # Did it work?
    if ($reply) {
        my $rcode = $reply->header->rcode;
        print 'Update ', $rcode eq 'NOERROR' ? "succeeded\n" : "failed: $rcode\n";
    } else {
        print 'Update failed: ', $res->errorstring, "\n";
    }

Add an MX record for a name that already exists¶

    my $update = Net::DNS::Update->new('example.com');
    $update->push(prerequisite => 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 = Net::DNS::Update->new('example.com');
    $update->push(prerequisite => 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 = Net::DNS::Update->new('example.com');
    $update->push(prerequisite => yxrrset('foo.example.com A'));
    $update->push(update       => rr_del('foo.example.com A'));

Delete all RRs for a name¶

    my $update = Net::DNS::Update->new('example.com');
    $update->push(prerequisite => yxdomain('byebye.example.com'));
    $update->push(update       => rr_del('byebye.example.com'));

Perform a signed update¶

    my $key_name = 'tsig-key';
    my $key_data = 'awwLOtRfpGE+rRKF2+DEiw==';
    my $update = Net::DNS::Update->new('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_data);

Another way to perform a signed update¶

    my $key_name = 'tsig-key';
    my $key_data = 'awwLOtRfpGE+rRKF2+DEiw==';
    my $update = Net::DNS::Update->new('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'));
    $update->push(additional => Net::DNS::RR->new("$key_name TSIG $key_data"));

Perform a signed update with a customized TSIG record¶

    my $key_name = 'tsig-key';
    my $key_data = 'awwLOtRfpGE+rRKF2+DEiw==';
    my $tsig = Net::DNS::RR->new("$key_name TSIG $key_data");
    $tsig->fudge(60);
    my $update = Net::DNS::Update->new('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);