title: Enabling sticky sessions with nginx ingress, not working
body: <p>I have a v1.8.4 deployment running nginx ingress controller. I had an ingress which works fine. But now I am trying to enable sticky sessions in it. I used <code>kubectl edit ing mying</code> to add these annotations:</p>
  
  <pre><code>nginx.ingress.kubernetes.io/affinity: cookie
  nginx.ingress.kubernetes.io/session-cookie-hash: md5
  nginx.ingress.kubernetes.io/session-cookie-name: foobar
  </code></pre>
  
  <p>But sticky sessions are still not working. Nginx config does not have anything about sticky sessions. Also, <code>kubectl describe ing mying</code> does not show the annotations. What is going wrong here?</p>
  
  <p>I also tried the example for sticky sessions <a href="https://github.com/kubernetes/ingress-nginx/tree/27c863085e2503e5f3249b596f24529fc2488baa/docs/examples/affinity/cookie" rel="nofollow noreferrer">here</a>.
  Describing the ingress does not show the annotations.</p>