Pass the Cloudera CCAH CCA-500 Questions and answers with CertsForce

Execute hdfs namenode –report on the command line and look at the Last Checkpoint information

Execute hdfs dfsadmin –saveNamespace on the command line which returns to you the last checkpoint value in fstime file

Connect to the web UI of the Secondary NameNode (http://mysecondary:50090/) and look at the “Last Checkpoint” information

Connect to the web UI of the NameNode (http://mynamenode:50070) and look at the “Last Checkpoint” information

nn02 is fenced, and nn01 becomes the active NameNode

nn01 is fenced, and nn02 becomes the active NameNode

nn01 becomes the standby NameNode and nn02 becomes the active NameNode

nn02 becomes the standby NameNode and nn01 becomes the active NameNode

The file will remain under-replicated until the administrator brings that node back online

The cluster will re-replicate the file the next time the system administrator reboots the NameNode daemon (as long as the file’s replication factor doesn’t fall below)

This will be immediately re-replicated and all other HDFS operations on the cluster will halt until the cluster’s replication values are resorted

The file will be re-replicated automatically after the NameNode determines it is under-replicated based on the block reports it receives from the NameNodes

Configure the NodeManager to enable MapReduce services on YARN by setting the following property in yarn-site.xml:

yarn.nodemanager.hostname

your_nodeManager_shuffle

Configure the NodeManager hostname and enable node services on YARN by setting the following property in yarn-site.xml:

yarn.nodemanager.hostname

your_nodeManager_hostname

Configure a default scheduler to run on YARN by setting the following property in mapred-site.xml:

mapreduce.jobtracker.taskScheduler

org.apache.hadoop.mapred.JobQueueTaskScheduler

Configure the number of map tasks per jon YARN by setting the following property in mapred:

mapreduce.job.maps

2

Configure the ResourceManager hostname and enable node services on YARN by setting the following property in yarn-site.xml:

yarn.resourcemanager.hostname

your_resourceManager_hostname

Configure MapReduce as a Framework running on YARN by setting the following property in mapred-site.xml:

mapreduce.framework.name

yarn

Because there is a more than a single job on the cluster, the FIFO Scheduler will enforce a limit on the percentage of resources allocated to a particular job at any given time

Tasks are scheduled on the order of their job submission

The order of execution of job may vary

Given job A and submitted in that order, all tasks from job A are guaranteed to finish before all tasks from job B

The FIFO Scheduler will give, on average, and equal share of the cluster resources over the job lifecycle

The FIFO Scheduler will pass an exception back to the client when Job B is submitted, since all slots on the cluster are use

Delete the /dev/vmswap file on the node

Delete the /etc/swap file on the node

Set the ram.swap parameter to 0 in core-site.xml

Set vm.swapfile file on the node

Delete the /swapfile file on the node

Add another master node to increase the number of nodes running the JournalNode which increases the number of machines available to HA to create a quorum

Set an HDFS replication factor that provides data redundancy, protecting against node failure

Run a Secondary NameNode on a different master from the NameNode in order to provide automatic recovery from a NameNode failure.

Run the ResourceManager on a different master from the NameNode in order to load-share HDFS metadata processing

Configure the cluster’s disk drives with an appropriate fault tolerant RAID level

You must modify the configuration files on the NameNode only. DataNodes read their configuration from the master nodes

You must modify the configuration files on each of the DataNodes machines

You don’t need to restart any daemon, as they will pick up changes automatically

You must restart the NameNode daemon to apply the changes to the cluster

You must restart all six DatNode daemon to apply the changes to the cluster