use Net::OpenSSH;

my $ssh = Net::OpenSSH->new('root@172.16.100.27', passphrase => 'blah', key_path => 'key.txt');
$ssh->error and 
	die "Couldn't establish SSH connection: ". $ssh->error;

$ssh->system('ifconfig em1');
$ssh->system('ifconfig -d');
$ssh->system('su - admin');

$ssh->system("show status");
$ssh->system('exit');
$ssh->system('exit');