title: Nginx Reverse Proxy upstream not working
body: <p>I'm having trouble figuring out load balancing on Nginx. I'm using:
  - Ubuntu 16.04 and
  - Nginx 1.10.0.</p>
  
  <p>In short, when I pass my ip address directly into "proxy_pass", the proxy works:</p>
  
  <pre><code>server {
      location / {
              proxy_pass http://01.02.03.04;
      }
  }
  </code></pre>
  
  <p>When I visit my proxy computer, I can see the content from the proxy ip...
  but when I use an upstream directive, it doesn't:</p>
  
  <pre><code>upstream backend {
       server 01.02.03.04;
  }
  
  server {
      location / {
              proxy_pass http://backend;
      }
  }
  </code></pre>
  
  <p>When I visit my proxy computer, I am greeted with the default Nginx server page and not the content from the upstream ip address.</p>
  
  <p>Any further assistance would be appreciated. I've done a ton of research but can't figure out why "upstream" is not working. I don't get any errors. It just doesn't proxy.</p>