title: how to check if sshd runs on a remote machine
body: <pre><code>ssh -q -o "BatchMode=yes" user@host "echo 2&gt;&amp;1" &amp;&amp; echo "OK" || echo "NOK"
  </code></pre>
  
  <p>this method is suitable but it returns <code>true</code> when the pub.key is copied to host.
  I need to see if an ssh is connectiable between two devices without keys.</p>
  
  <p>Simply wants to check if the sshd is running remotely.</p>