title: HDFS vs LFS - How Hadoop Dist. File System is built over local file system?
body: <p>From various blogs I read, I comprehended that HDFS is another layer that exists over Local filesystem in a computer.</p>
  
  <p>I also installed hadoop but I have trouble understanding the existence of hdfs layer over local file system.</p>
  
  <p>Here is my question..</p>
  
  <p>Consider I am installing hadoop in pseudo-distributed mode. What happens under the hood during this installation? I added a tmp.dir parameter in configuration files. Is is the single folder to which namenode daemon talks to, when it attemps to access the datanode??</p>