CCA-470 試験問題を無料オンラインアクセス

Under which of the following scenarios would it be most appropriate to consider using faster (e.g., 10 Gigabit) Ethernet as the network fabric for your Hadoop cluster?

• A.When the typical workload consists of processor-intensive tasks.
• B.When the typical workload generates a large amount of output data, significantly larger than the amount of intermediate data.
• C.When the typical workload consumes a large amount of input data, relative to the entire Canada of HDFS.
• D.When the typical workload generates a large amount of intermediate data, on the order of the input data itself.

You have a cluster running with the Fair Scheduler enabled and configured. You submit multiple jobs to cluster. Each job is assigned to a pool. How are jobs scheduled? (Choose 2)

• A.Each pool gets 1/M of the total available task slots, where M is the number of nodes in the cluster
• B.Each pool's share of task slots remains static within the execution of any individual job.
• C.Pools are assigned priorities. Pools with higher priorities are executed before pools with lower priorities.
• D.Pools get a dynamically-allocated share of the available task slots (subject to additional constraints).
• E.Each pool's share of task slots may change throughout the course of job execution.
• F.Each pool gets 1/N of the total available task slots, where N is the number of jobs running on the cluster.

You are running a Hadoop cluster with all monitoring facilities properly configured. Which scenario will go undetected?

• A.MapReduce jobs that are causing excessive memory swaps.
• B.The NameNode goes down.
• C.Map or reduce tasks that are stuck in an infinite loop.
• D.HDFS is almost full.
• E.A DataNode is disconnected from the cluster.

Which command does Hadoop offer to discover missing or corrupt HDFS data?

• A.The map-only checksum utility,
• B.Dskchk
• C.Fsck
• D.Du
• E.Hadoop does not provide any tools to discover missing or corrupt data; there is no need because three replicas are kept for each data block.

You set up the Hadoop cluster using NameNode Federation. One NameNode manages the/users namespace and one NameNode manages the/data namespace. What happens when client tries to write a file to/reports/myreport.txt?

• A.The file successfully writes to /users/reports/myreports/myreport.txt.
• B.The file successfully writes to /report/myreport.txt. The metadata for the file is managed by the first NameNode to which the client connects.
• C.The file writes fails silently; no file is written, no error is reported.
• D.The client throws an exception.