title: Sockets.IO only works in localhost
body: <p>Here's my codes</p>
  
  <pre><code>const brokerService = require('socket.io')({
      path: '/broker',
      serveClient: false
  });
  
  exports.assignServices = function ()
  {
      brokerService.listen(3003);
  }
  
  brokerService.on("connection" , (client) =&gt; {
      console.log("connected");
  
      client.on("test" , (data) =&gt; {
          console.log(data);
      });
  
      client.on("add" , (data) =&gt; {
          console.log(data); 
      });
  })
  </code></pre>
  
  <p>I use application called socket-io-tester on my MAC</p>
  
  <p>it sends packets to my localhost with this URL (<a href="http://127.0.0.1.com:3003/broker" rel="nofollow noreferrer">http://127.0.0.1.com:3003/broker</a>)</p>
  
  <p>and my application logged "Connected" - works now</p>
  
  <p>but after uploading my app to digitalocean servers , it does not work anymore</p>
  
  <p>with the same app I send to the same URL , but replacing the ip to my domain name (<a href="http://domainName.com:3003/broker" rel="nofollow noreferrer">http://domainName.com:3003/broker</a>)</p>
  
  <p>it does not work ?</p>
  
  <p>same code / same URL request / same application I use to test</p>
  
  <p>may the issue with my server?</p>
  
  <p>I turned off the firewall , is it related anyway ?</p>