#!/usr/bin/perl -w
use strict;

use vars qw($last_status);

sub run_external {
    my $cmd = shift;
    print "Running [$cmd]";
    $last_status = system($cmd);
    $last_sys_error = $?;
    return $last_status
};

run_external(<<COMMAND);
    command1 param1=value1 param2=value2
COMMAND

for my $machine (@machines) {
    run_external(<<COMMAND);
    command1 machine=$machine param1=value1 param2=value2
COMMAND

    if ($last_status) {
        run_external(<<COMMAND);
              debugging_command machine=$machine debug_param1=debug_value1
COMMAND
    };
};