Environment variables for IBM Spectrum Symphony Advanced Edition

IBM® Spectrum Symphony Advanced Edition provides the most support for distributed compute-and data- intensive applications To use specific product features, you must have IBM Spectrum Symphony Advanced Edition entitlement and be familiar with environment variables for your system.

To enable the IBM Spectrum Symphony Advanced Edition product features, a cluster administrator must set the following environment variables. Any variables set in the environment overwrite the same variables set in the configuration file. Set environment variables using any of these methods:

To define cluster properties as environment variables with bash, run:
```
export VARIABLE_NAME=value
```
To define cluster properties as environment variables with csh, run:
```
setenv VARIABLE_NAME value
```
To define cluster properties in a file, create a simple text file (such as /tmp/install.config), and enter each variable on a new line, as follows:
```
VARIABLE_NAME=value
```

The environment variables you can set for IBM Spectrum Symphony Advanced Edition are applicable enabling the MapReduce framework with IBM Spectrum Symphony, and integrating YARN with IBM Spectrum Symphony. Both of these features are supported on Linux®.

Environment variables for MapReduce integration

INSTALL_MAPREDUCE

Required to install MapReduce. Specify Y. For example:

For bash: export INSTALL_MAPREDUCE=Y
For csh: setenv INSTALL_MAPREDUCE Y

If not set, or if specified to N, MapReduce is not installed.

JAVA_HOME

Specifies the directory under which Oracle or IBM Java is installed. For example:

For bash: export JAVA_HOME=/usr/java/latest
For csh: setenv JAVA_HOME /usr/java/latest

Your Java installation location is required for enabling the MapReduce framework. You can do this by setting the JAVA_HOME environment variable before installing IBM Spectrum Symphony.

If you install IBM Spectrum Symphony without setting the JAVA_HOME environment variable, you can do so at a later date by defining the JAVA_HOME in the $SOAM_HOME/mapreduce/conf/pmr-env.sh file. (See pmr-env.sh reference for details.)

HADOOP_HOME

Specifies the directory under which the Hadoop distribution is installed.

For example:

For bash: export HADOOP_HOME=/opt/hadoop-2.7.2
For csh: setenv HADOOP_HOME /opt/hadoop-2.7.2

HADOOP_VERSION

Specifies the version of the Hadoop distribution in your cluster:

For example:

For bash: export HADOOP_VERSION=2_7_2
For csh: setenv HADOOP_VERSION=2_7_2

DFS_GUI_HOSTNAME

Specifies the host name of the HDFS NameNode, enabling you to view the HDFS web interface within the cluster management console. If you plan to configure high availability for the HDFS NameNode, so that the cluster management console can redirect the HDFS web interface to the new NameNode host when failover occurs. For example:

For bash: export DFS_GUI_HOSTNAME=namenodehost.mydomain.com
For csh: setenv DFS_GUI_HOSTNAME namenodehost.mydomain.com

IBM Spectrum Symphony only enables you to connect to the HDFS web interface through the cluster management console. It does not provide any security mechanism for HDFS through IBM Spectrum Symphony. Be aware that some information, such as the web server version, may be exposed through this interface.

DFS_GUI_PORT

Specifies the port that the HDFS NameNode web interface will use. For example:

For bash: export DFS_GUI_PORT=50070
For csh: setenv DFS_GUI_PORT 50070

Note: Permissions for operating system users in a multi-user environment: for a multi-user configuration, ensure the following prerequisites if you change the default operating system user for the MapReduceConsumer consumer (to which MapReduce applications are registered by default):

All execution users for the MapReduceConsumer must belong to the same user group as the cluster administrator.
If you are using the Hadoop Distributed File System (HDFS), the cluster administrator must ensure the following setup:
- Permissions for the operating system user must match permissions set for the work, input, and output directories in HDFS.
- The operating system user must have write permissions to access the HDFS directory defined by the hadoop.tmp.dir parameter in the Hadoop configuration files core-default.xml or coresite.xml.

Environment variables for YARN integration

JAVA_HOME

Specifies the directory under which Oracle or IBM Java is installed. For example:

For bash: export JAVA_HOME=/usr/java/latest
For csh: setenv JAVA_HOME /usr/java/latest

Your Java installation location is required for integrating YARN with IBM Spectrum Symphony. You can do this by setting the JAVA_HOME environment variable before installing IBM Spectrum Symphony.

If you install IBM Spectrum Symphony without setting the JAVA_HOME environment variable, you can do so at a later date by defining the JAVA_HOME in the $EGO_TOP/integration/yarn/conf/egoyarn-env.sh file. (See egoyarn-env.sh reference for details.)

HADOOP_YARN_HOME

Specifies the directory under which Apache Hadoop YARN is installed. For example:

For bash: export HADOOP_YARN_HOME=/opt/hadoop-Hadoop_version
For csh: setenv HADOOP_YARN_HOME /opt/hadoop-Hadoop_version

To enable IBM Spectrum Symphony-YARN integration, you must first have a full distribution of YARN installed and properly configured.