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. The zone and class may be undefined or omitted and default to the default domain from the resolver configuration and IN respectively.

push¶

    $ancount = $update->push( prereq => $rr );
    $nscount = $update->push( update => $rr );
    $arcount = $update->push( additional => $rr );
    $nscount = $update->push( update => $rr1, $rr2, $rr3 );
    $nscount = $update->push( update => @rr );

Adds RRs to the specified section of the update packet.

Returns the number of resource records in the specified section.

Section names may be abbreviated to the first three characters.

unique_push¶

    $ancount = $update->unique_push( prereq => $rr );
    $nscount = $update->unique_push( update => $rr );
    $arcount = $update->unique_push( additional => $rr );
    $nscount = $update->unique_push( update => $rr1, $rr2, $rr3 );
    $nscount = $update->unique_push( update => @rr );

Adds RRs to the specified section of the update packet provided that the RRs are not already present in the same section.

Returns the number of resource records in the specified section.

Section names may be abbreviated to the first three characters.

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 does not 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 private key file¶

    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 );