title: name node Vs secondary name node
body: <p>Hadoop is Consistent and partition tolerant, i.e. It falls under the CP category of the CAP theoram.</p>
  
  <p>Hadoop is not available because all the nodes are dependent on the name node. If the name node falls the cluster goes down.</p>
  
  <p>But considering the fact that the HDFS cluster has a secondary name node why cant we call hadoop as available. If the name node is down the secondary name node can be used for the writes.</p>
  
  <p>What is the major difference between name node and secondary name node that makes hadoop unavailable.</p>
  
  <p>Thanks in advance. </p>