You need to perform statistical analysis in your MapReduce job and would like to call methods in the Apache Commons Math library, which is distributed as a 1.3 megabyte Java archive (JAR) file.
Which is the best way to make this library available to your MapReducer job at runtime?
A . Have your system administrator copy the JAR to all nodes in the cluster and set its location in the HADOOP_CLASSPATH environment variable before you submit your job.
B . Have your system administrator place the JAR file on a Web server accessible to all cluster nodes and then set the HTTP_JAR_URL environment variable to its location.
C . When submitting the job on the command line, specify the Clibjars option followed by the JAR file path.
D . Package your code and the Apache Commands Math library into a zip file named JobJar.zip
Answer: C
Explanation:
The usage of the jar command is like this,
Usage: hadoop jar <jar> [mainClass] args…
If you want the commons-math3.jar to be available for all the tasks you can do any one of these
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