Cloudera CCA-500 Braindumps 2021

NEW QUESTION 1
Your Hadoop cluster contains nodes in three racks. You have not configured the dfs.hosts property in the NameNode’s configuration file. What results?

• A. The NameNode will update the dfs.hosts property to include machines running the DataNode daemon on the next NameNode reboot or with the command dfsadmin–refreshNodes
• B. No new nodes can be added to the cluster until you specify them in the dfs.hosts file
• C. Any machine running the DataNode daemon can immediately join the cluster
• D. Presented with a blank dfs.hosts property, the NameNode will permit DataNodes specified in mapred.hosts to join the cluster

Answer: C

NEW QUESTION 2
Your cluster’s mapred-start.xml includes the following parameters
<name>mapreduce.map.memory.mb</name>
<value>4096</value>
<name>mapreduce.reduce.memory.mb</name>
<value>8192</value>
And any cluster’s yarn-site.xml includes the following parameters
<name>yarn.nodemanager.vmen-pmen-ration</name>
<value>2.1</value>
What is the maximum amount of virtual memory allocated for each map task before YARN will kill its Container?

• A. 4 GB
• B. 17.2 GB
• C. 8.9 GB
• D. 8.2 GB
• E. 24.6 GB

Answer: D

NEW QUESTION 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. Capacity Scheduler
• C. Fair Scheduler
• D. FIFO Scheduler

Answer: C

Explanation: Reference:http://hadoop.apache.org/docs/r1.2.1/fair_scheduler.html

NEW QUESTION 4
You are configuring your cluster to run HDFS and MapReducer v2 (MRv2) on YARN. Which two daemons needs to be installed on your cluster’s master nodes?(Choose two)

• A. HMaster
• B. ResourceManager
• C. TaskManager
• D. JobTracker
• E. NameNode
• F. DataNode

Answer: BE

NEW QUESTION 5
Cluster Summary:
45 files and directories, 12 blocks = 57 total. Heap size is 15.31 MB/193.38MB(7%)

Refer to the above screenshot.
You configure a Hadoop cluster with seven DataNodes and on of your monitoring UIs displays the details shown in the exhibit.
What does the this tell you?

• A. The DataNode JVM on one host is not active
• B. Because your under-replicated blocks count matches the Live Nodes, one node is dead, and your DFS Used % equals 0%, you can’t be certain that your cluster has all the data you’ve written it.
• C. Your cluster has lost all HDFS data which had bocks stored on the dead DatNode
• D. The HDFS cluster is in safe mode

Answer: A

NEW QUESTION 6
You are working on a project where you need to chain together MapReduce, Pig jobs. You also need the ability to use forks, decision points, and path joins. Which ecosystem project should you use to perform these actions?

• A. Oozie
• B. ZooKeeper
• C. HBase
• D. Sqoop
• E. HUE

Answer: A

NEW QUESTION 7
You decide to create a cluster which runs HDFS in High Availability mode with automatic failover, using Quorum Storage. What is the purpose of ZooKeeper in such a configuration?

• A. It only keeps track of which NameNode is Active at any given time
• B. It monitors an NFS mount point and reports if the mount point disappears
• C. It both keeps track of which NameNode is Active at any given time, and manages the Edits fil
• D. Which is a log of changes to the HDFS filesystem
• E. If only manages the Edits file, which is log of changes to the HDFS filesystem
• F. Clients connect to ZooKeeper to determine which NameNode is Active

Answer: A

Explanation: Reference: Reference:http://www.cloudera.com/content/cloudera-content/cloudera-docs/CDH4/latest/PDF/CDH4-High-Availability-Guide.pdf(page 15)

NEW QUESTION 8
Your cluster implements HDFS High Availability (HA). Your two NameNodes are named nn01 and nn02. What occurs when you execute the command: hdfs haadmin –failover nn01 nn02?

• A. nn02 is fenced, and nn01 becomes the active NameNode
• B. nn01 is fenced, and nn02 becomes the active NameNode
• C. nn01 becomes the standby NameNode and nn02 becomes the active NameNode
• D. nn02 becomes the standby NameNode and nn01 becomes the active NameNode

Answer: B

Explanation: failover – initiate a failover between two NameNodes
This subcommand causes a failover from the first provided NameNode to the second. If the first
NameNode is in the Standby state, this command simply transitions the second to the Active statewithout error. If the first NameNode is in the Active state, an attempt will be made to gracefullytransition it to the Standby state. If this fails, the fencing methods (as configured bydfs.ha.fencing.methods) will be attempted in order until one of the methods succeeds. Only afterthis process will the second NameNode be transitioned to the Active state. If no fencing methodsucceeds, the second NameNode will not be transitioned to the Active state, and an error will bereturned.

NEW QUESTION 9
Choose three reasons why should you run the HDFS balancer periodically?(Choose three)

• A. To ensure that there is capacity in HDFS for additional data
• B. To ensure that all blocks in the cluster are 128MB in size
• C. To help HDFS deliver consistent performance under heavy loads
• D. To ensure that there is consistent disk utilization across the DataNodes
• E. To improve data locality MapReduce

Answer: CDE

Explanation: http://www.quora.com/Apache-Hadoop/It-is-recommended-that-you-run-the-HDFS-balancer-periodically-Why-Choose-3

NEW QUESTION 10
Which process instantiates user code, and executes map and reduce tasks on a cluster running MapReduce v2 (MRv2) on YARN?

• A. NodeManager
• B. ApplicationMaster
• C. TaskTracker
• D. JobTracker
• E. NameNode
• F. DataNode
• G. ResourceManager

Answer: A

NEW QUESTION 11
What two processes must you do if you are running a Hadoop cluster with a single NameNode and six DataNodes, and you want to change a configuration parameter so that it affects all six DataNodes.(Choose two)

• A. You must modify the configuration files on the NameNode onl
• B. DataNodes read their configuration from the master nodes
• C. You must modify the configuration files on each of the six SataNodes machines
• D. You don’t need to restart any daemon, as they will pick up changes automatically
• E. You must restart the NameNode daemon to apply the changes to the cluster
• F. You must restart all six DatNode daemon to apply the changes to the cluster

Answer: BD

NEW QUESTION 12
Your Hadoop cluster is configuring with HDFS and MapReduce version 2 (MRv2) on YARN. Can you configure a worker node to run a NodeManager daemon but not a DataNode daemon and still have a functional cluster?

• A. Ye
• B. The daemon will receive data from the NameNode to run Map tasks
• C. Ye
• D. The daemon will get data from another (non-local) DataNode to run Map tasks
• E. Ye
• F. The daemon will receive Map tasks only
• G. Ye
• H. The daemon will receive Reducer tasks only

Answer: B

NEW QUESTION 13
Your cluster is running MapReduce version 2 (MRv2) on YARN. Your ResourceManager is configured to use the FairScheduler. Now you want to configure your scheduler such that a new user on the cluster can submit jobs into their own queue application submission. Which configuration should you set?

• A. You can specify new queue name when user submits a job and new queue can be created dynamically if the property yarn.scheduler.fair.allow-undecleared-pools = true
• B. Yarn.scheduler.fair.user.fair-as-default-queue = false and yarn.scheduler.fair.allow- undecleared-pools = true
• C. You can specify new queue name when user submits a job and new queue can be created dynamically if yarn .schedule.fair.user-as-default-queue = false
• D. You can specify new queue name per application in allocations.xml file and have new jobs automatically assigned to the application queue

Answer: A

NEW QUESTION 14
You have just run a MapReduce job to filter user messages to only those of a selected geographical region. The output for this job is in a directory named westUsers, located just below your home directory in HDFS. Which command gathers these into a single file on your local file system?

• A. Hadoop fs –getmerge –R westUsers.txt
• B. Hadoop fs –getemerge westUsers westUsers.txt
• C. Hadoop fs –cp westUsers/* westUsers.txt
• D. Hadoop fs –get westUsers westUsers.txt

Answer: B

NEW QUESTION 15
Which is the default scheduler in YARN?

• A. YARN doesn’t configure a default scheduler, you must first assign an appropriate scheduler class in yarn-site.xml
• B. Capacity Scheduler
• C. Fair Scheduler
• D. FIFO Scheduler

Answer: B

Explanation: Reference:http://hadoop.apache.org/docs/r2.4.1/hadoop-yarn/hadoop-yarn-site/CapacityScheduler.html

NEW QUESTION 16
You need to analyze 60,000,000 images stored in JPEG format, each of which is approximately 25 KB. Because you Hadoop cluster isn’t optimized for storing and processing many small files, you decide to do the following actions:
1. Group the individual images into a set of larger files
2. Use the set of larger files as input for a MapReduce job that processes them directly with python using Hadoop streaming.
Which data serialization system gives the flexibility to do this?

• A. CSV
• B. XML
• C. HTML
• D. Avro
• E. SequenceFiles
• F. JSON

Answer: E

Explanation: Sequence files are block-compressed and provide direct serialization and deserialization of several arbitrary data types (not just text). Sequence files can be generated as the output of other MapReduce tasks and are an efficient intermediate representation for data that is passing from one MapReduce job to anther.