Hadoop Online Quiz

Q 1 - In a Hadoop cluster, what is true for a HDFS block that is no longer available due to disk corruption or machine failure?

A - It is lost for ever

B - It can be replicated form its alternative locations to other live machines.

C - The namenode allows new client request to keep trying to read it.

D - The Mapreduce job process runs ignoring the block and the data stored in it.

Q 2 - In Hadoop 2.x release HDFS federation means

A - Allowing namenodes to communicate with each other.

B - Allow a cluster to scale by adding more datanodes under one namenode.

C - Allow a cluster to scale by adding more namenodes.

D - Adding more physical memory to both namenode and datanode.

Q 3 - HDFS can be accessed over HTTP using

A - viewfs URI scheme

B - webhdfs URI scheme

C - wasb URI scheme

D - HDFS ftp

Q 4 - Which of the below property gets configured on mapred-site.xml ?

A - Replication factor

B - Directory names to store hdfs files.

C - Host and port where MapReduce task runs.

D - Java Environment variables.

Q 5 - The input split used in MapReduce indicates

A - The average size of the data blocks used as input for the program

B - The location details of where the first whole record in a block begins and the last whole record in the block ends.

C - Splitting the input data to a MapReduce program into a size already configured in the mapred-site.xml

D - None of these

Q 6 - Running Start-dfs.sh results in

A - Starting namenode and datanode

B - Starting namenode only

C - Starting datanode only

D - Starting namenode and resource manager

Q 7 - The archive file created in Hadoop always has the extension of

A - .hrc

B - .har

C - .hrh

D - .hrar

Q 8 - Which one is not one of the big data feature?

A - Velocity

B - Veracity

C - volume

D - variety

Q 9 - When using HDFS, what occurs when a file is deleted from the command line?

A - It is permanently deleted if trash is enabled.

B - It is placed into a trash directory common to all users for that cluster.

C - It is permanently deleted and the file attributes are recorded in a log file.

D - It is moved into the trash directory of the user who deleted it if trash is enabled.

Q 10 - Which one of the following statements is true regarding <key,value> pairs of a MapReduce job?

A - A key class must implement Writable.

B - A key class must implement WritableComparable.

C - A value class must implement WritableComparable.

D - A value class must extend WritableComparable.