Engineering Questions with Answers - Multiple Choice Questions
MCQs on Introduction to HDFS
1 - Question
A ________ serves as the master and there is only one NameNode per cluster.
a) Data Node
b) NameNode
c) Data block
d) Replication
View Answer
Answer: b
Explanation: All the metadata related to HDFS including the information about data nodes, files stored on HDFS, and Replication, etc. are stored and maintained on the NameNode.
2 - Question
Point out the correct statement.
a) DataNode is the slave/worker node and holds the user data in the form of Data Blocks
b) Each incoming file is broken into 32 MB by default
c) Data blocks are replicated across different nodes in the cluster to ensure a low degree of fault tolerance
d) None of the mentioned
View Answer
Answer: a
Explanation: There can be any number of DataNodes in a Hadoop Cluster.
3 - Question
HDFS works in a __________ fashion.
a) master-worker
b) master-slave
c) worker/slave
d) all of the mentioned
View Answer
Answer: a
Explanation: NameNode servers as the master and each DataNode servers as a worker/slave
4 - Question
________ NameNode is used when the Primary NameNode goes down.
a) Rack
b) Data
c) Secondary
d) None of the mentioned
View Answer
Answer: c
Explanation: Secondary namenode is used for all time availability and reliability.
5 - Question
Point out the wrong statement.
a) Replication Factor can be configured at a cluster level (Default is set to 3) and also at a file level
b) Block Report from each DataNode contains a list of all the blocks that are stored on that DataNode
c) User data is stored on the local file system of DataNodes
d) DataNode is aware of the files to which the blocks stored on it belong to
View Answer
Answer: d
Explanation: NameNode is aware of the files to which the blocks stored on it belong to.
6 - Question
Which of the following scenario may not be a good fit for HDFS?
a) HDFS is not suitable for scenarios requiring multiple/simultaneous writes to the same file
b) HDFS is suitable for storing data related to applications requiring low latency data access
c) HDFS is suitable for storing data related to applications requiring low latency data access
d) None of the mentioned
View Answer
Answer: a
Explanation: HDFS can be used for storing archive data since it is cheaper as HDFS allows storing the data on low cost commodity hardware while ensuring a high degree of fault-tolerance.
7 - Question
The need for data replication can arise in various scenarios like ____________
a) Replication Factor is changed
b) DataNode goes down
c) Data Blocks get corrupted
d) All of the mentioned
View Answer
Answer: d
Explanation: Data is replicated across different DataNodes to ensure a high degree of fault-tolerance.
8 - Question
________ is the slave/worker node and holds the user data in the form of Data Blocks.
a) DataNode
b) NameNode
c) Data block
d) Replication
View Answer
Answer: a
Explanation: A DataNode stores data in the [HadoopFileSystem]. A functional filesystem has more than one DataNode, with data replicated across them.
9 - Question
HDFS provides a command line interface called __________ used to interact with HDFS.
a) “HDFS Shell”
b) “FS Shell”
c) “DFS Shell”
d) None of the mentioned
View Answer
Answer: b
Explanation: The File System (FS) shell includes various shell-like commands that directly interact with the Hadoop Distributed File System (HDFS).
10 - Question
HDFS is implemented in _____________ programming language.
a) C++
b) Java
c) Scala
d) None of the mentioned
View Answer
Answer: b
Explanation: HDFS is implemented in Java and any computer which can run Java can host a NameNode/DataNode on it.
Explanation: HDFS is implemented in Java and any computer which can run Java can host a NameNode/DataNode on it.
11 - Question
For YARN, the ___________ Manager UI provides host and port information.
a) Data Node
b) NameNode
c) Resource
d) Replication
View Answer
Answer: c
Explanation: All the metadata related to HDFS including the information about data nodes, files stored on HDFS, and Replication, etc. are stored and maintained on the NameNode.
12 - Question
Point out the correct statement.
a) The Hadoop framework publishes the job flow status to an internally running web server on the master nodes of the Hadoop cluster
b) Each incoming file is broken into 32 MB by default
c) Data blocks are replicated across different nodes in the cluster to ensure a low degree of fault tolerance
d) None of the mentioned
View Answer
Answer: a
Explanation: The web interface for the Hadoop Distributed File System (HDFS) shows information about the NameNode itself.
13 - Question
For ________ the HBase Master UI provides information about the HBase Master uptime.
a) HBase
b) Oozie
c) Kafka
d) All of the mentioned
View Answer
Answer: a
Explanation: HBase Master UI provides information about the number of live, dead and transitional servers, logs, ZooKeeper information, debug dumps, and thread stacks.
14 - Question
During start up, the ___________ loads the file system state from the fsimage and the edits log file.
a) DataNode
b) NameNode
c) ActionNode
d) None of the mentioned
View Answer
Answer: b
Explanation: HDFS is implemented on any computer which can run Java can host a NameNode/DataNode on it.