A couple of thoughts...

If you have no idea which "$ThirdOctet's the servers are on, then I don't see where you would have any choice but to cycle through them all. Either give it a list of them directly (see below) or you if you can parse it from /etc/hosts, build it dynamically. 
#! /usr/local/bin/perl -w                                
                                                         
use strict;                                              
use Net::Ping;                                           
                                                         
my $IPBlk;                                               
my $FirstOctets = "10.0";                                
my @ValidOctets = (1, 5, 7);                                
     

foreach my $ThirdOctet (@ValidOctets) {
    my $sbnt = "$FirstOctets." . "$ThirdOctet" . ".0";
    print "Pinging: $sbnt\n";
    my $p = Net::Ping->new();
    if ($p->ping("$sbnt") ) {
        print "host exists\n";
    } else {
        print "Host does not exist\n";
    }
    print "$?\n";
}

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If you can parse /etc/hosts it might pay to put a distinguishing comment on the lines that are servers (### SERVER ###). You could then parse the file for these entries and build a list of known servers to ping via their direct address. Don't know it this is exactly what you are looking to accomplish, but you might want to try that approach instead. Might take some work to fix up your /etc/hosts file, but it would be a one-timer.

-THRAK
www.polarlava.com

In reply to Re: Using Net::Ping for broadcast address by THRAK
in thread Using Net::Ping for broadcast address by birdbrane

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