title: 'Operation timed out' error on trying to ssh in to the Amazon EMR Spark Cluster
body: <p>I'm trying to ssh into Amazon EMR Spark Cluster. Here's what I did:</p>
  
  <ol>
  <li><p>Get the cluster master's IP:</p>
  
  <pre><code>aws emr describe-cluster --cluster-id &lt;cluster_id&gt; | grep MasterPublicDnsName
  </code></pre></li>
  <li><p>Use the IP to ssh into the box:</p>
  
  <pre><code>ssh -i CSxxx.pem hadoop@ec2-xx-xxx-xxx-xxx.ap-southeast-1.compute.amazonaws.com
  </code></pre></li>
  </ol>
  
  <p>I'm getting stuck here, as running (2) gives me the below error:</p>
  
  <pre><code>ssh: connect to host ec2-xx-xxx-xxx-xxx.ap-southeast-1.compute.amazonaws.com port 22: Operation timed out
  </code></pre>
  
  <p>Any ideas to fix this issue?</p>