Find below the list of Hadoop interview questions and answers jotted down to help job seekers
Question: What is Hadoop and its workings?
Answer: When “Big Data” appeared as problematic, Apache Hadoop changed as an answer to it. Apache Hadoop is a context which offers us numerous facilities or tools to store and development of Big Data. It benefits in analysing Big Data and creation business decisions out of it, which can’t be done professionally and successfully using old-style systems.
Question: What is the usage of Hadoop?
Answer: With Hadoop, the employer can run requests on the systems that have thousands of bulges scattering through countless terabytes. Rapid data dispensation and assignment among nodes helps continuous operation even when a node fails averting system let-down.
Question: On what idea, the Hadoop framework runs?
Answer: Hadoop Framework acts upon the subsequent two core components-
1)HDFS – Hadoop Distributed File System is the java based file system for ascendable and consistent storage of great datasets. Data in HDFS is kept in the form of blocks and it functions on the Master Slave Architecture.
2)Hadoop MapReduce-This is a java based software design paradigm of Hadoop framework that delivers scalability across numerous Hadoop clusters. MapReduce allocates the assignment into numerous tasks that can route in parallel.
Hadoop jobs accomplish 2 separate tasks- job. The map job disruptions down the data sets into key-value pairs or tuples. The decrease job then receipts the output of the map job and syndicates the data tuples to into lesser set of tuples. The lessen job is always achieved after the map job is performed.
Question: What are the basic features of Hadoop?
Answer: Inscribed in Java, Hadoop framework has the competence of resolving questions involving Big Data analysis. Its program design model is based on Google MapReduce and substructure is based on Google’s Big Data and dispersed file systems. Hadoop is ascendable and more nodes can be implemented to it.
Question: What is the finest hardware configuration to run Hadoop?
Answer: The finest formation for performing Hadoop jobs is double core machines or dual mainframes with 4GB or 8GB RAM that practice ECC memory. Hadoop extremely assistances from using ECC recollection though it is not low – end. ECC memory is suggested for running Hadoop since most of the Hadoop users have skilled various checksum faults by using non ECC memory. Though, the hardware formation also be subject to on the workflow necessities and can change consequently.