title: How to handle mqtt disconnection on Node-RED?
body: <p>I'm implementing a draft of a connection between 2 Raspberry and an Arduino, connected via mqtt. I'm working on Node-RED flows and I used mqtt nodes.</p>
  <p>As you can see, in mqtt node configuration there is the possibility to send different messages for specific moments (when the subscriber is online, when it goes offline and when it disconnects unexpectedly.
  I'd like to catch this last event and handle it. How can I do it?</p>
  <p><a href="https://i.stack.imgur.com/GSB4B.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/GSB4B.png" alt="enter image description here" /></a></p>