CURSO: ADMINISTRADOR PARA APACHE HADOOP

Transcription

1 CURSO: ADMINISTRADOR PARA APACHE HADOOP TEST DE EJEMPLO DEL EXÁMEN DE CERTIFICACIÓN

2 1 Question: 1 A developer has submitted a long running MapReduce job with wrong data sets. You want to kill the running MapReduce job so that a new job with the correct data sets can be started. What method can be used to terminate the submitted MapReduce job? A. Use CTRL-C from the terminal where the MapReduce job was started. B. Open a remote terminal to the node running the ApplicationMaster and kill the JVM. C. hadoop datanode -rollback D. yarn application -kill <application_id> Answer: D 2

3 2 Question: 2 A specific node in your cluster appears to be running slower than other nodes with the same hardware configuration. You suspect that the system is swapping memory to disk due to over allocation of resources. Which commands may be used to view the memory and swap usage on the system? A. jps B. lsswap C. top D. memusage E. free F. Df E. vmstat Answer: C, E, E 3

4 3 Question: 3 What must you do if you are running a Hadoop cluster with a single NameNode and six DataNodes, and you wish to change the configuration of all DataNodes. A. You must restart the NameNode daemon to apply the changes to the cluster. B. You must modify the configuration files on your NameNode where the master configuration files reside for all DataNodes. C. You must restart all six DataNode daemons to apply the changes. D. You don t need to restart any daemon, as they will pick up changes automatically. Answer: C 4

5 4 Question: 4 You are running a Hadoop cluster with a NameNode on host mynamenode. What are two ways you can determine available HDFS space in your cluster? A. Connect to and locate the DFS Remaining value. B. Run hdfs dfsadmin -SpaceQuota and subtract DFS Used% from Configured Capacity. C. Run hdfs dfsadmin -report and locate the DFS Remaining value. D. Run hadoop fs -du / and locate the DFS Remaining Answer: A,C 5

6 5 Question: 5 You set the value of mapred.child.java.opts to -Xmx200M on all TaskTrackers in the cluster. You set the same configuration parameter to -Xmx500M on the JobTracker. What size heap will a Map task running on the cluster have? A. 64MB B. 128MB C. 200MB D. 256MB E. 500MB F. The job will fail because of the discrepancy Answer: C 6

7 6 Question: 6 After a file has been written to HDFS, which of the following operations can you perform? A. You can delete the file B. You can update the file s contents C. You can overwrite the file by creating a new file with the same name D. You can move the file E. You can rename the file Answer: A,D,E 7

8 7 Question: 7 Identify which is a recommended configuration of disk drives for a DataNode? A. 48 2TB disk drives in a RAID configuration B. One 3TB disk drive C. 12 1TB disk drives in a RAID configuration D. 12 2TB disk drives in a JBOD configuration Answer: D 8

9 8 Question: 8 Which tool is best suited to import a portion of a relational database every day as files into HDFS, and generate Java classes to interact with that imported data? A. Pig B. Hive C. Sqoop D. Hue E. Flume F. Oozie Answer: C 9

10 9 Question: 9 The NameNode needs to know which DataNodes hold each HDFS block. How is that block location information managed? A. The DataNodes communicate block locations to each other, peer-to-peer on startup and every 60 minutes (a changeable parameter) called the block report. B. The NameNode stores the block locations in RAM and in the fsimage file. C. The NameNode stores the block locations in the fsimage file only. D. The NameNode stores the block locations in RAM. They are never stored on disk. Answer: D 10

11 10 Question: 10 Identify the function performed by a Secondary NameNode daemon configured to run with a single NameNode. A. It combines the fsimage and edits files produced by the NameNode. B. It acts as a standby NameNode, providing a high availability profile for clients. C. It provides an alternate HDFS endpoint when the NameNode is too busy. D. It performs real-time backups of the NameNode. Answer: A 11

12 Contacto TWITTER Twitter.com/formacionhadoop FACEBOOK Facebook.com/formacionhadoop LINKEDIN linkedin.com/company/formación-hadoop 12