what daemons run on a master node and slave nodes?

381

mapper or reducer?

622

Explain what does the conf.setmapper class do?

340

When Namenode is down what happens to job tracker?

446

What is the difference between Reducer and Combiner in Hadoop MapReduce?

377

Explain the input type/format in mapreduce by default?

342

What is an identity mapper and identity reducer?

345

How is mapreduce related to cloud computing?

342

Describe what happens to a mapreduce job from submission to output?

360

What is heartbeat in hdfs?

395

Detail description of the Reducer phases?

578

Is it legal to set the number of reducer task to zero? Where the output will be stored in this case?

372

What is MapReduce in Hadoop?

359

Compare Pig vs Hive vs Hadoop MapReduce?

366

Is there any point of learning mapreduce, then?

386