title: Redirect a domain to a ip and port
body: <p>I have a node.js server listening on port 4000</p>
  
  <p>how can I redirect  my domain name: www.mydomain.com to a ip and port? The domain provider only allows an ip address without a portnumber in the redirection field. If I do a URL redirect, then the name of my side is not shown.</p>
  
  <p>Please let me know how can I redirect it to my domain?</p>
  
  <pre><code>121.12.12.123:4000    redirect to   www.mydomain.com
  </code></pre>