#!/usr/bin/perl 
use POSIX;  
 
my $dns_txt = '/home/otpuser/dns.txt'; 
open (INFILE, "$dns_txt" || die "cant open $!\n"); 
  
while ($line = <INFILE>) 
        { 
        chomp($line); 
        $line =~ s/(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/$1$2$3$4/; 
        print "$1.$2.$3.$4\n"; 
	}

 
$line =~ s/.*?client\s(\d+)\.(\d+).(\d+).(\d+)#.*/$1$2$3$4/;  
Or  
$line =~ s/.*?client\s(\d{1,3})\.(\d{1,3}).(\d{1,3}).(\d{1,3})#.*/$1$2$3$4/;

# Not tested, adjust the indices if necessary 
my @fields=(split(/(#|:\s+|\s+)/,$line))[3,6];

#!/usr/bin/perl 
use POSIX; 
my $dns_txt = '/home/otpuser/dns.txt'; 
  
open (INFILE, "$dns_txt" || die "cant open $!\n"); 
  
my @fields=<INFILE>; 
  
chomp @fields; 
  
foreach $line (@fields) 
        { 
        @ip=(split(/(#|:\s+|\s+)/,$line))[6,12]; 
        print "@ip\n"; 
        } 
print "----------\n"; 
print scalar @fields, " scalar fields \n"; 
print scalar @ip, " scalar ip \n";

#!/usr/bin/perl 
 
use strict; 
use warnings; 
 
my $dns_txt = '/home/otpuser/dns.txt'; 
open my $dns_fh, '<', $dns_txt or die "cant open $!\n"; 
 
my (%ip, %host); 
while (my $line = <$dns_fh>) { 
    my ($ip, $host) = (split(/(#|:\s+|\s+)/,$line))[6,12];  
    $ip{$ip}++; 
    $host{$host}++; 
} 
close $dns_fh; 
 
# output the counts as needed

use strict; 
use warnings;

foreach $value (sort {$host{$b} <=> $host{$a} } keys %host) 
{ 
     print "$value $host{$value}\n"; 
}

print scalar @ip;

my $ip_cnt = keys %ip; 
print "Total number of unique ip addresses:$ip_cnt\n"; 
 
my $host_cnt = keys %host; 
print "Total number of unique hosts:$host_cnt\n";