1. Which hdfs command is used to check for various inconsistencies?
a) fsk
b) fsck
c) fetchdt
d) none of the mentioned
Explanation: fsck is designed for reporting problems with various files, for example, missing blocks for a file or under-replicated blocks.
2. Point out the correct statement.
a) All hadoop commands are invoked by the bin/hadoop script
b) Hadoop has an option parsing framework that employs only parsing generic options
c) Archive command creates a hadoop archive
d) All of the mentioned
Explanation: Running the hadoop script without any arguments prints the description for all commands.
3. HDFS supports the ____________ command to fetch Delegation Token and store it in a file on the local system.
a) fetdt
b) fetchdt
c) fsk
d) rec
Explanation: Delegation token can be later used to access secure server from a non secure client.
4. In ___________ mode, the NameNode will interactively prompt you at the command line about possible courses of action you can take to recover your data.
a) full
b) partial
c) recovery
d) commit
Explanation: Recovery mode can cause you to lose data, you should always backup your edit log and fsimage before using it.
5. Point out the wrong statement.
a) classNAME displays the class name needed to get the Hadoop jar
b) Balancer Runs a cluster balancing utility
c) An administrator can simply press Ctrl-C to stop the rebalancing process
d) None of the mentioned
Explanation: classpath prints the class path needed to get the Hadoop jar and the required libraries.
6. _________ command is used to copy file or directories recursively.
a) dtcp
b) distcp
c) dcp
d) distc
Explanation: Usage of the distcp command: hadoop distcp <srcurl> <desturl>.
7. __________ mode is a Namenode state in which it does not accept changes to the name space.
a) Recover
b) Safe
c) Rollback
d) None of the mentioned
Explanation: dfsadmin runs a HDFS dfsadmin client.
8. __________ command is used to interact and view Job Queue information in HDFS.
a) queue
b) priority
c) dist
d) all of the mentioned
Explanation: Hadoop script can be used to invoke any class.
9. Which of the following command runs the HDFS secondary namenode?
a) secondary namenode
b) secondarynamenode
c) secondary_namenode
d) none of the mentioned
Explanation: The secondary NameNode merges the fsimage and the edits log files periodically and keeps edits log size within a limit.
10. Which of the following is used for the MapReduce job Tracker node?
a) mradmin
b) tasktracker
c) jobtracker
d) none of the mentioned
Explanation: tasktracker runs a MapReduce task Tracker node.