On CSD-based deployments, Cloudera Manager automatically detects the path and version of Java installed on Cloudera Data Science Workbench gateway hosts.
You do not need to explicitly set the value for
JAVA_HOME unless you want to use a custom location, use JRE, or (in the case of
Spark 2) force Cloudera Manager to use JDK 1.8 as explained below.
Setting a value for JAVA_HOME - The value for
JAVA_HOME depends on whether you are using JDK or
JRE. For example, if you're using JDK 1.8_162, set
If you are only using JRE, set it to
Issues with Spark 2.2 and higher - Spark 2.2 (and higher) requires JDK 1.8. However, if a host has both JDK 1.7 and JDK 1.8 installed, Cloudera Manager might choose to use JDK 1.7 over JDK 1.8. If you are using Spark 2.2 (or higher), this will create a problem during the first run of the service because Spark will not work with JDK 1.7. To work around this, explicitly configure Cloudera Manager to use JDK 1.8 on the gateway hosts that are running Cloudera Data Science Workbench.
For instructions on how to set
JAVA_HOME, see Configuring a Custom Java Home Location
in Cloudera Manager.
To upgrade the whole CDH cluster to JDK 1.8, see Upgrading to JDK 1.8.