Here is a list of MapReduce Interview questions asked in all Hadoop and Bigdata jobs interview questions. For more interview questions check this link.
MapReduce Interview Questions
Explain about MapReduce Framework?
Explain different ways of debugging a job in MapReduce?
Write a Mapreduce Program for Character Count ?
Can we submit the mapreduce job from slave node?
What is the InputSplit in map reduce ?
How to overwrite an existing output file during execution of mapreduce jobs?
Explain about mapper and reducer phases ?
Explain the Reducer Sort phase?
Which interface needs to be implemented to create Mapper and Reducer for the Hadoop?
Why comparison of types is important for MapReduce?
Is YARN a replacement of Hadoop MapReduce?