title: Netcat can't connect to a port from an external IP
body: <p>I have 2 machines, I try to send a JSON request from machine2 to machine1.</p>
  
  <p>When I do</p>
  
  <pre><code>echo '{"name": "app_01", "output": "THIS WILL WORK", "status": 1}' | nc localhost 3030
  </code></pre>
  
  <p>It works fine. I receive my request in my log file.
  But when I try to to the same on my machine2, I have a <code>Connection Refused</code> error.</p>
  
  <pre><code>echo '{"name": "app_01", "output": "THIS WILL NOT WORK", "status": 1}' | nc 192.168.10.134 3030
  </code></pre>
  
  <p>My 2 machines are in the same local network.
  Do you have an idea why it doesn't work? </p>
  
  <p>Thanks.</p>