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- what is the "2" in print "$host is dead\n" unless $p->ping($host, 2);?
According to the documentation for Net::Ping, the "2" is a timeout value: 
$p->ping($host [, $timeout]);

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Ping the remote host and wait for a response. $host can be either the hostname or the IP number of the remote host. The optional timeout must be greater than 0 seconds and defaults to whatever was specified when the ping object was created.
is there any shortcut way to put this in the @array?
I'm not sure what you mean by shortcut, but qw is handy for constructing arrays (note the absence of double quotes and commas): 
my @array = qw(4.4.4.4 127.0.0.1 123.333.333.333);

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Another general tip: add these to the top of your code: 

use warnings;
use strict;

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I have no answer for your 1st question :(

In reply to Re: Net::Ping issues by toolic
in thread Net::Ping issues by chris_henderson

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