Hadoop Online Quiz

Q 1 - HDFS block size is larger as compared to the size of the disk blocks so that

A - Only HDFS files can be stored in the disk used.

B - The seek time is maximum

C - Transfer of a large files made of multiple disk blocks is not possible.

D - A single file larger than the disk size can be stored across many disks in the cluster.

Q 2 - The datanode and namenode are respectiviley

A - Master and worker nodes

B - Worker and Master nodes

C - Both are worker nodes

D - None

Q 3 - The following is not permitted on HDFS files

A - Deleting

B - Renaming

C - Moving

D - Executing.

Q 4 - The file in Namenode which stores the information mapping the data block location with file name is −

A - dfsimage

B - nameimage

C - fsimage

D - image

Q 5 - If the IP address or hostname of a datanode changes

A - The namenode updates the mapping between file name and block name

B - The namenode need not update mapping between file name and block name

C - The data in that data node is lost forever

D - There namenode has to be restarted

Q 6 - The command “hadoop fs -test -z URI “ gives the result 0 if

A - if the path is a directory

B - if the path is a file

C - if the path is not empty

D - if the file is zero length

Q 7 - All the files in a directory in HDFS can be merged together using

A - getmerge

B - putmerge

C - remerge

D - mergeall

Q 8 - The number of tasks a task tracker can accept depends on

A - Maximum memory available in the node

B - Not limited

C - Number of slots configured in it

D - As decided by the jobTracker

Q 9 - How does Hadoop process large volumes of data?

A - Hadoop uses a lot of machines in parallel. This optimizes data processing.

B - Hadoop was specifically designed to process large amount of data by taking advantage of MPP hardware.

C - Hadoop ships the code to the data instead of sending the data to the code.

D - Hadoop uses sophisticated caching techniques on name node to speed processing of data.

Q 10 - When writing data to HDFS what is true if the replication factor is three? (Choose 2 answers)

1. Data is written to DataNodes on three separate racks (if Rack Aware).

2. The Data is stored on each DataNode with a separate file which contains a checksum value.

3. Data is written to blocks on three different DataNodes.

4. The Client is returned with a success upon the successful writing of the first block and checksum check.

A - 1 & 3

B - 2 & 3

C - 3 & 4

D - 1 & 4