title: Nginx reverse proxy load upstream list from external file
body: <p>I'm writing an automation to add new servers to the upstream.
  Currently my upstream block is embedded in the reverse proxy configuration file with a <code>proxy_pass  http://backbones;</code> directive in the <code>server</code> block.</p>
  
  <p>I would like to separate the upstream block to a different file so it will be easier to parse it.</p>
  
  <p>Is it possible to load the upstream block from a different file?</p>
  
  <p>Thanks,
  Liron</p>