title: Private docker registry on Kubernetes not visible to other pods
body: <p>I have a CoreOS base Kubernetes deployment.  I followed the instruction on GitHub to set up a private Docker registry:
  <a href="https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/registry/README.md" rel="nofollow">https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/registry/README.md</a></p>
  
  <p>The registry came up and the registry proxy also came up:</p>
  
  <pre><code>$ kubectl get po --namespace=kube-system
  NAME                              READY     STATUS    RESTARTS   AGE
  kube-dns-v9-hd0hz                 4/4       Running   0          1d
  kube-registry-proxy-10.1.52.113   1/1       Running   0          1d
  kube-registry-proxy-10.1.52.114   1/1       Running   0          1d
  kube-registry-proxy-10.1.52.117   1/1       Running   0          1d
  kube-registry-proxy-10.1.52.118   1/1       Running   0          1d
  kube-registry-v0-ib8vx            1/1       Running   0          1d
  kubernetes-dashboard-17zfm        1/1       Running   0          1d
  </code></pre>
  
  <p>I was also able to push private image using the port-forward method (port forward to either the registry pod or the registry proxy pod.)  But when I try to use the image, I get PullImageError:</p>
  
  <pre><code>kubectl run -i --tty ubuntu --image=localhost:5000/myfirstubuntu/ubuntu --restart=Never -- bash
  </code></pre>
  
  <p>And if I just create a new container with plain ubuntu and try to curl localhost:5000, I don't get the 404 error as shown in the instruction so looks like the pod on the same node is not talking to the registry-proxy as expected.  What are the ways to further debug this?</p>