Hi All,
I've just knocked together a quick script to check the reverse DNS entries for a /16. It's purpose is to print any IP addres that doesn't have a reverse entry (currently I'm not worried about forward and reverse entries being the same).

I've written the following, but would be interested in a "better" way of doing this:

#!/usr/bin/perl

use Net::DNS

$res = Net::DNS::Resolver->new;

for($c = 0; $c <= 255; $c++) {
 for($d = 0; $d <= 255; $d++) {
  $query= $res->query("81.86.$c.$d", "PTR");
  print "81.86.$c.$d" unless $query;
 }
}

[download]

Anyone who fancies a quick blast at Perl golf, but all means put on you spikey shoes and silly clothes and swing away.

!unlike

I write my Perl code like how I like my sex: fast and dirty. ;)

edited: Tue Apr 22 14:18:43 2003 by jeffa - title change (was: Seeking a better way)

In reply to Better way to check reverse DNS entries by !unlike

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