#!/usr/bin/perl
use strict;
use warnings;

use Net::IP qw/ip_iptobin/;

my %temphash = (
  '1AHIT' => { COMMENT => '1AHIT', IP => '192.168.221.10' },
  '2AHIT' => { COMMENT => '2AHIT', IP => '192.168.222.10' },
  'CAD1-OST' => { COMMENT => 'CAD1-OST', IP => '192.168.43.10' }
);

my @keys_sorted_by_ip = sort {
  ip_iptobin($temphash{$a}{IP}, 4) cmp ip_iptobin($temphash{$b}{IP}, 4)
} keys %temphash;

print map { "$_: IP = $temphash{$_}{IP}\n" } @keys_sorted_by_ip;