title: Use random id in Apache config
body: <p>I am trying to track unique requests in my application (PHP) and access (Apache) logs.</p>
  
  <p>My proposed solution:</p>
  
  <ol>
  <li>Apache generates a unique id and sets it as a header or environment variable.</li>
  <li>PHP uses the the header/environment variable in its logging.</li>
  <li><code>mod_log_config</code> uses the value in its logging.</li>
  </ol>
  
  <p>This way, I can track the activity of a single request in logs.</p>
  
  <p>But I'm not sure how I can do the first part (or even if I can).</p>
  
  <p>Can I configure Apache to generate a sufficiently unique (random) identifier for each request?</p>