title: NGINX and load balancing with 404 error
body: <p>I am using nginx for reverse proxy and load balancing. 
  I can see page jump between myapp.com and google.com, but it only display 404 not found page, not the main page.
  The config is below:</p>
  
  <p>upstream backend </p>
  
  <pre><code>server myapp.com;
  server www.google.com;
  </code></pre>
  
  <p>server </p>
  
  <pre><code>listen 80;
  location / {
      proxy_pass http://backend;
  }
  </code></pre>
  
  <p>Do you guys have any ideasabout the configuration issue?</p>