title: How to debug when Kubernetes nodes are in 'Not Ready' state
body: <p>I initialized the master node and add 2 worker nodes, but only master and one of the worker node show up when I run the following command:</p>
  
  <pre><code>kubectl get nodes
  </code></pre>
  
  <p>also, both these nodes are in 'Not Ready' state. 
  What are the steps should I take to understand what the problem could be?</p>
  
  <ul>
  <li>I can ping all the nodes from each of the other nodes. </li>
  <li>The version of Kubernetes is 1.8.</li>
  <li>OS is Cent OS 7</li>
  <li><p>I used the following repo to install Kubernetes:</p>
  
  <pre><code>cat &lt;&lt;EOF &gt; /etc/yum.repos.d/kubernetes.repo
  [kubernetes] name=Kubernetes
  baseurl=http://yum.kubernetes.io/repos/kubernetes-el7-x86_64
  enabled=1
  gpgcheck=0
  repo_gpgcheck=0
  EOF
  
  yum install kubelet kubeadm kubectl kubernetes-cni
  </code></pre></li>
  </ul>