use Net::DNS;
my $res = Net::DNS::Resolver->new(debug=>0,
                                  igntc=>1,
				  recurse=>1,
				  retrans=>0,
				  retry=>1);
$res->port($nameserverport);
$res->nameservers("$nameserver");
$res->usevc(1);
$res->tcp_timeout($timeout);
$res->srcaddr($srcaddr);
$res->srcport($srcport);
my %result_set = ();
my $ttl = 0x7fffffff;
#Query type is "A" ,"MX" ,"CNAME"
my $query = Net::DNS::Packet->new($address, "A");
my $response = $res->send($query);
if ($response->header->ancount > 0) {
  foreach my $rr ($response->answer) {
    my $rr_addr;
   if ($rr->type eq $querytype && $querytype eq "A"){
      $rr_addr = $rr->address;
   }
     if ($rr_addr) {
          $result_set->{$rr_addr} = 1;
          push(@result, $rr_addr);
          $ttl = $rr->ttl unless ($ttl < $rr->ttl);
    }
 }
}