#!/usr/bin/perl -w
use strict;
use Net::SSH qw(ssh);

use constant USER => 'root';
use constant CMD => '/usr/local/scripts/temp.sh';
 
for my $host (qw(
    192.168.15.2
    192.168.16.2
    192.168.17.2
    192.168.18.2
)) {
    (ssh(USER . '@' . $host, CMD) != 256)
        and last;
    warn "No response from $host\n";
}