Which of the following are among the duties of the Data Nodes in HDFS?

Question

A - Maintain the file system tree and metadata for all files and directories.

B - None of the options is correct.

C - Control the execution of an individual map task or a reduce task.

D - Store and retrieve blocks when told to by clients or the NameNode.

E - Manage the file system namespace.

Answer 1

The correct answer is option D (store and retrieve blocks when told by clients or the name node). Because the DataNode acts as a slave in Hadoop Cluster whereas NameNode acts as a Master. DataNode stores the business data, creating, replicating, deleting, retrieving data blocks as per the instructions of Master (NameNode).

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