How do you define "block" in HDFS?
What Mapper does?
What is the difference between Hadoop and Traditional RDBMS?
What are active and passive "NameNodes"?
What is a block and block scanner in HDFS?
Explain the use of tasktracker in the hadoop cluster?
How does an hadoop application look like or their basic components?
Explain the hadoop-core configuration?
What if a namenode has no data?
Did you ever built a production process in hadoop ? If yes then what was the process when your hadoop job fails due to any reason?
shouldn't DFS be able to handle large volumes of data already?
What is rack-aware replica placement policy?
Does this lead to security issues?