Cloudera CCA-500 問題集

質問 1：
Identify two features/issues that YARN is designated to address:
A. Ability to run framework other than MapReduce, such as MPI
B. Resource pressure on the JobTracker
C. HDFS latency
D. Standardize on a single MapReduce API
E. Reduce complexity of the MapReduce APIs
F. Single point of failure in the NameNode
正解：B,F
解説: (Topexam メンバーにのみ表示されます)

質問 2：
You are migrating a cluster from MApReduce version 1 (MRv1) to MapReduce version 2 (MRv2) on YARN. You want to
maintain your MRv1 TaskTracker slot capacities when you migrate. What should you do/
A. Configure yarn.applicationmaster.resource.memory-mb and
yarn.applicationmaster.resource.cpu-vcores so that ApplicationMaster container allocations match the capacity you
require.
B. Configure yarn.nodemanager.resource.memory-mb and yarn.nodemanager.resource.cpuvcores to match the
capacity you require under YARN for each NodeManager
C. Configure mapred.tasktracker.map.tasks.maximum and mapred.tasktracker.reduce.tasks.maximum ub yarn-site.xml
to match your cluster's capacity set by the yarn-scheduler.minimum-allocation
D. You don't need to configure or balance these properties in YARN as YARN dynamically balances resource
management capabilities on your cluster
正解：B

質問 3：
Which scheduler would you deploy to ensure that your cluster allows short jobs to finish within a reasonable time
without starting long-running jobs?
A. Complexity Fair Scheduler (CFS)
B. FIFO Scheduler
C. Fair Scheduler
D. Capacity Scheduler
正解：C
解説: (Topexam メンバーにのみ表示されます)

質問 4：
You are running a Hadoop cluster with a NameNode on host mynamenode, a secondary NameNode on host
mysecondarynamenode and several DataNodes.
Which best describes how you determine when the last checkpoint happened?
A. Execute hdfs namenode -report on the command line and look at the Last Checkpoint information
B. Connect to the web UI of the NameNode (http://mynamenode:50070) and look at the "Last Checkpoint"
information
C. Connect to the web UI of the Secondary NameNode (http://mysecondary:50090/) and look at the "Last
Checkpoint" information
D. Execute hdfs dfsadmin -saveNamespace on the command line which returns to you the last checkpoint value in
fstime file
正解：D
解説: (Topexam メンバーにのみ表示されます)

質問 5：
You're upgrading a Hadoop cluster from HDFS and MapReduce version 1 (MRv1) to one running HDFS and MapReduce
version 2 (MRv2) on YARN. You want to set and enforce version 1 (MRv1) to one running HDFS and MapReduce
version 2 (MRv2) on YARN. You want to set and enforce a block size of 128MB for all new files written to the cluster
after upgrade. What should you do?
A. Set dfs.block.size to 128 M on all the worker nodes and client machines, and set the parameter to final. You do not
need to set this value on the NameNode
B. You cannot enforce this, since client code can always override this value
C. Set dfs.block.size to 134217728 on all the worker nodes, on all client machines, and on the NameNode, and set the
parameter to final
D. Set dfs.block.size to 128M on all the worker nodes, on all client machines, and on the NameNode, and set the
parameter to final
E. Set dfs.block.size to 134217728 on all the worker nodes and client machines, and set the parameter to final. You do
not need to set this value on the NameNode
正解：A

質問 6：
You suspect that your NameNode is incorrectly configured, and is swapping memory to disk. Which Linux commands
help you to identify whether swapping is occurring?
A. swapinfo
B. free
C. jps
D. memcat
E. vmstat
F. top
G. df
正解：B,E,F
解説: (Topexam メンバーにのみ表示されます)