Free CCA-500: Cloudera Certified Administrator for Apache Hadoop (CCAH) Exam Questions and Answers

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/

• AA. Configure yarn.applicationmaster.resource.memory-mb and yarn.applicationmaster.resource.cpu-vcores so that ApplicationMaster container allocations match the capacity you require.
• BB. You don’t need to configure or balance these properties in YARN as YARN dynamically balances resource management capabilities on your cluster
• CC. 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
• DD. Configure yarn.nodemanager.resource.memory-mb and yarn.nodemanager.resource.cpu-vcores to match the capacity you require under YARN for each NodeManager

You have a Hadoop cluster HDFS, and a gateway machine external to the cluster from which clients submit jobs. What do you need to do in order to run Impala on the cluster and submit jobs from the command line of the gateway machine?

• AA. Install the impalad daemon statestored daemon, and daemon on each machine in the cluster, and the impala shell on your gateway machine
• BB. Install the impalad daemon, the statestored daemon, the catalogd daemon, and the impala shell on your gateway machine
• CC. Install the impalad daemon and the impala shell on your gateway machine, and the statestored daemon and catalogd daemon on one of the nodes in the cluster
• DD. Install the impalad daemon on each machine in the cluster, the statestored daemon and catalogd daemon on one machine in the cluster, and the impala shell on your gateway machine
• EE. Install the impalad daemon, statestored daemon, and catalogd daemon on each machine in the cluster and on the gateway node

You observed that the number of spilled records from Map tasks far exceeds the number of map output records. Your child heap size is 1GB and your io.sort.mb value is set to 1000MB. How would you tune your io.sort.mb value to achieve maximum memory to disk I/O ratio?

• AA. For a 1GB child heap size an io.sort.mb of 128 MB will always maximize memory to disk I/O
• BB. Increase the io.sort.mb to 1GB
• CC. Decrease the io.sort.mb value to 0
• DD. Tune the io.sort.mb value until you observe that the number of spilled records equals (or is as close to equals) the number of map output records.

You are planning a Hadoop cluster and considering implementing 10 Gigabit Ethernet as the network fabric. Which workloads benefit the most from faster network fabric?

• AA. When your workload generates a large amount of output data, significantly larger than the amount of intermediate data
• BB. When your workload consumes a large amount of input data, relative to the entire capacity if HDFS
• CC. When your workload consists of processor-intensive tasks
• DD. When your workload generates a large amount of intermediate data, on the order of the input data itself

A slave node in your cluster has 4 TB hard drives installed (4 x 2TB). The DataNode is configured to store HDFS blocks on all disks. You set the value of the dfs.datanode.du.reserved parameter to 100 GB. How does this alter HDFS block storage?

• AA. 25GB on each hard drive may not be used to store HDFS blocks
• BB. 100GB on each hard drive may not be used to store HDFS blocks
• CC. All hard drives may be used to store HDFS blocks as long as at least 100 GB in total is available on the node
• DD. A maximum if 100 GB on each hard drive may be used to store HDFS blocks

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?

• AA. Execute hdfs namenode –report on the command line and look at the Last Checkpoint information
• BB. Execute hdfs dfsadmin –saveNamespace on the command line which returns to you the last checkpoint value in fstime file
• CC. Connect to the web UI of the Secondary NameNode (http://mysecondary:50090/) and look at the “Last Checkpoint” information
• DD. Connect to the web UI of the NameNode (http://mynamenode:50070) and look at the “Last Checkpoint” information

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

• AA. 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
• BB. No new nodes can be added to the cluster until you specify them in the dfs.hosts file
• CC. Any machine running the DataNode daemon can immediately join the cluster
• DD. Presented with a blank dfs.hosts property, the NameNode will permit DataNodes specified in mapred.hosts to join the cluster

Identify two features/issues that YARN is designated to address:(Choose two)

Select 2 answers.

• AA. Standardize on a single MapReduce API
• BB. Single point of failure in the NameNode
• CC. Reduce complexity of the MapReduce APIs
• DD. Resource pressure on the JobTracker
• EE. Ability to run framework other than MapReduce, such as MPI
• FF. HDFS latency

Assuming a cluster running HDFS, MapReduce version 2 (MRv2) on YARN with all settings at their default, what do you need to do when adding a new slave node to cluster?

• AA. Nothing, other than ensuring that the DNS (or/etc/hosts files on all machines) contains any entry for the new node.
• BB. Restart the NameNode and ResourceManager daemons and resubmit any running jobs.
• CC. Add a new entry to /etc/nodes on the NameNode host.
• DD. Restart the NameNode of dfs.number.of.nodes in hdfs-site.xml

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?

• AA. Oozie
• BB. ZooKeeper
• CC. HBase
• DD. Sqoop
• EE. HUE