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Which version of java is used in CM-cluster?

Expert Contributor

Hi everyone, which version of java is used in the cluster?


I found:




Is the one with "cloudera" the used one?

Because java -version gives:

java version "1.6.0_31"
Java(TM) SE Runtime Environment (build 1.6.0_31-b04)
Java HotSpot(TM) 64-Bit Server VM (build 20.6-b01, mixed mode)

Thus I am not sure if Cloudera Manager and other tools are configured to use jdk 6 or 7.



Thanks for any info


Re: Which version of java is used in CM-cluster?




Please run the below command, it will show you which java version being used currently





Re: Which version of java is used in CM-cluster?

Super Guru



As mentioned, if JAVA_HOME is set, that is generally what java procesess on the hosts will use.  If JAVA_HOME is not set then the process will do its best to identify the release to use.


If you wish, you can remove the java versions you do not need.


The JVM versions you are using are old.  I recommend you consider installing the latest supported JVM release for your verison of CM/CDH.


For more information on supported JDKs:


For more information regarding installation of a JDK:


Steps to configure a CDH and Management Service to use a specific JDK:


We recommend removing any JDKs from your system if they are not what you want to use.

The JDK versions you have now were installed from Cloudera's package repository, but they are older and Cloudera does not intend to supply newer releases in its repository.  Since JDK 1.6 is only installed to support legacy CDH 4 clusters, you can safely remove JDK 1.6.0_31 from your system unless you are using it for some other purpose (not CDH).


If you have specific questions, please let us know


Re: Which version of java is used in CM-cluster?

Expert Contributor

Thank you for the answer


The JAVA_HOME is not set, and I've installed the jdk version from the CDH repository. Then I guess the Cloudera Manager also installed the jdk 6 during the isntallation/configuration phase.


So you recommend to uninstall jdk 6 and 7 and install the latest supported jdk on each host?