5.2. Install HDP

Use the following instructions to install HDP on your cluster hardware. Ensure that you specify the virtual machine (configured in the previous section) as your NameNode.

Download Hortonworks Data Platform (HDP) using the instructions provided here.
Note
Do not start the server until you have configured the relevant templates as outlined in the following steps.

	Note
Do not start the server until you have configured the relevant templates as outlined in the following steps.

Add the configuration parameters for Full-Stack HA.

Edit the<master-install-machine-for-HDP>/etc/puppet/master/modules/hdp-hadoop/templates/hdfs-site.xml.erb file to add the following properties:

Enable the HDFS client retry policy.

<property>
 <name>dfs.client.retry.policy.enabled</name>
 <value>true</value>
 <description> Enables HDFS client retry in case of NameNode failure.</description>
</property>

Configure protection for NameNode edit log.

<property>
 <name>dfs.namenode.edits.toleration.length</name>
 <value>8192</value>
 <description> Prevents corruption of NameNode edit log.</description>
</property>

Configure safe mode extension time.

<property>
 <name>dfs.safemode.extension</name>
 <value>10</value>
 <description> The default value (30 seconds) is applicable for very large clusters. For small to large clusters (upto 200 nodes), recommended value is 10 seconds.</description>
</property>

Ensure that the allocated DFS blocks persist across multiple fail overs.

<property>
 <name>dfs.persist.blocks</name>
 <value>true</value>
 <description> Ensure that the allocated DFS blocks persist across   multiple fail overs.</description>
</property>

Configure delay for first block report.

<property>
 <name>dfs.blockreport.initialDelay</name>
 <value>10</value>
 <description> Delay (in seconds) for first block report. </description>
</property>

Edit the<master-install-machine-for-HDP>/etc/puppet/master/modules/hdp-hadoop/templates/mapred-site.xml.erb file to add the following properties:

Enable the JobTracker’s safe mode functionality.

<property>
 <name>mapreduce.jt.hdfs.monitor.enable</name>
 <value>true</value>
 <description> Enable the JobTracker to go into safe mode when the NameNode is unresponsive.</description>
</property>

Enable retry for JobTracker clients (when the JobTracker is in safe mode).

<property>
 <name>mapreduce.jobclient.retry.policy.enabled</name>
 <value>true</value>
 <description> Enable the MapReduce job client to retry job submission when the JobTracker is in safe
    mode.</description>
</property>

Enable recovery of JobTracker’s queue after it is restarted.

<property>
 <name>mapred.jobtracker.restart.recover</name>
 <value>true</value>
 <description>  Enable the JobTracker to recover its queue after JobTracker is restarted.</description>
</property>

Edit the<master-install-machine-for-HDP>/etc/puppet/master/modules/hdp-hadoop/templates/core-site.xml.erb file to add the following properties:
- Configure checkpoint interval so that the checkpoint is performed on an hourly basis.
```
<property>
 <name>fs.checkpoint.period</name>
 <value>3600</value>
 <description> The number of seconds between two periodic checkpoints.</description>
</property>
```

Complete HDP installation.

Continue the installation process using the instructions provided here.
Ensure that you also follow the instructions listed below:
- Use the fully qualified domain name (FQDN) of the virtual machine for configuring the host names (see: Installing, Configuring, and Deploying the Cluster - Assign Masters.).
  Note
  HDP might not identify the NameNode VM automatically and it is therefore important to note down FQDN (IP address and DNS name) of the NameNode VM.
- Specify shared storage for the NameNode’s directories (see: HDP (Ambari) - Customize Services).
- Do not use the NameNode VM for running any other master daemon.

	Note
HDP might not identify the NameNode VM automatically and it is therefore important to note down FQDN (IP address and DNS name) of the NameNode VM.

Complete the HDP installation. Ensure that the installation was successful.

Note

	Note
To modify the parameters in the template files after you have installed HDP, ensure that you follow the instructions listed below: Change the template files as required. Stop and start the respective service through the Ambari console GUI. For example, stop and restart the MapReduce service if the `mapreduce-site.xml.erb` file is modified. Stop and restart HDFS service if either the `core-site.xml.erb` or the `hdfs-site.xml.erb` file is modified.

To modify the parameters in the template files after you have installed HDP, ensure that you follow the instructions listed below:

Change the template files as required.
Stop and start the respective service through the Ambari console GUI.
For example, stop and restart the MapReduce service if the mapreduce-site.xml.erb file is modified. Stop and restart HDFS service if either the core-site.xml.erb or the hdfs-site.xml.erb file is modified.

Legal notices