Hadoop Interview Questions and Answers

Ques 1. What is Hadoop?

Hadoop is a distributed computing platform. It is written in Java. It consists of the features like Google File System and MapReduce.

Ques 2. What platform and Java version are required to run Hadoop?

Java 1.6.x or higher versions are good for Hadoop, preferably from Sun. Linux and Windows are the supported operating system for Hadoop, but BSD, Mac OS/X, and Solaris are more famous for working.

Ques 3. What kind of Hardware is best for Hadoop?

Hadoop can run on a dual processor/ dual core machines with 4-8 GB RAM using ECC memory. It depends on the workflow needs.

Ques 4. What are the most common input formats defined in Hadoop?

These are the most common input formats defined in Hadoop:

1. TextInputFormat
2. KeyValueInputFormat
3. SequenceFileInputFormat

TextInputFormat is a by default input format.

Ques 5. How do you categorize a big data?

The big data can be categorized using the following features:

• Volume
• Velocity
• Variety