title: How can I debug "ImagePullBackOff"?
body: <p>All of a sudden, I cannot deploy some images which could be deployed before. I got the following pod status:</p>
  <pre><code>[root@webdev2 origin]# oc get pods 
  NAME                      READY     STATUS             RESTARTS   AGE 
  arix-3-yjq9w              0/1       ImagePullBackOff   0          10m 
  docker-registry-2-vqstm   1/1       Running            0          2d 
  router-1-kvjxq            1/1       Running            0          2d 
  </code></pre>
  <p>The application just won't start. The pod is not trying to run the container. From the Event page, I have got <code>Back-off pulling image &quot;172.30.84.25:5000/default/arix@sha256:d326</code>. I have verified that I can pull the image with the tag with <code>docker pull</code>.</p>
  <p>I have also checked the log of the last container. It was closed for some reason. I think the pod should at least try to restart it.</p>
  <p>I have run out of ideas to debug the issues. What can I check more?</p>