#!/usr/bin/perl
use strict;
use IO::All;
use warnings;
use Net::SSH2;
use Date::Manip;

my $datestr = ParseDate("now");
my $dateHumanReadable = UnixDate($datestr, "Date: %T on %b %e, %Y.");

#get ip’s
#open file
my @data = io("ips2.txt")->chomp->slurp;

my $ssh2 = Net::SSH2->new();

foreach my $sw (@data) {
    $ssh2->connect($sw, 22) or $ssh2->die_with_error;

    $ssh2->auth( publickey => "/home/user/.ssh/id_rsa");

    my $chan = $ssh2->channel()
	or $ssh2->die_with_error;

    $chan->blocking(1);

    $chan->exec("ls -la /home/user/Monks/Foo")
	or $ssh2->die_with_error;

    my ($out, $err) = ('', '');
    while (!$chan->eof) {
	if (my ($o, $e) = $chan->read2) {
	    $out .= $o;
	    $err .= $e;
	}
	else {
	    $ssh2->die_with_error;
	}
    }

    io("stdout-$sw.txt")->print("$dateHumanReadable\n\nSTDOUT:\n$out");
    io("stderr-$sw.txt")->print("STDERR:\n$err" .
				"exit status: " .
				$chan->exit_status .
				"\n");

    $ssh2->disconnect();
}

__END__

$ time perl test.pl

real	0m0.389s
user	0m0.127s
sys	0m0.028s
$ cat stdout-127.0.0.1.txt
Date: 14:14:30 on Aug  8, 2018.

STDOUT:
total 16
drwxrwxr-x  2 user user 4096 Feb 28 21:10 .
drwxrwxr-x 14 user user 4096 Aug  8 14:14 ..
-rw-rw-r--  1 user user  263 Feb 28 21:10 Bar.pm
-rw-rw-r--  1 user user  184 Jan 30  2018 Bar.pm~

$ cat stderr-127.0.0.1.txt
STDERR:
exit status: 0