Apache Cassandra™ 2.0

Installing Oracle JRE on RHEL-based Systems

You must configure your operating system to use the Oracle JRE, not the OpenJDK. The latest 64-bit version of Java 7 is recommended. The minimum supported version is 1.7.0_25.

Note: After installing the JRE, you may need to set JAVA_HOME to your profile:

For shell or bash: export JAVA_HOME=path_to_java_home

For csh (C shell): setenv JAVA_HOME=path_to_java_home

Procedure

  1. Check which version of the JRE your system is using:
    $ java -version

    If Oracle Java is used, the results should look like:

    java version "1.7.0_25"
    Java(TM) SE Runtime Environment (build 1.7.0_25-b15)
    Java HotSpot(TM) 64-Bit Server VM (build 23.25-b01, mixed mode)
  2. If necessary, go to Oracle Java SE Downloads, accept the license agreement, and download the installer for your distribution.
    Note: If installing the Oracle JRE in a cloud environment, accept the license agreement, download the installer to your local client, and then use scp (secure copy) to transfer the file to your cloud machines.
  3. From the directory where you downloaded the package, run the install:
    $ sudo rpm -ivh jre-7uversion-linux-x64.rpm

    The RPM installs the JRE into the /usr/java/ directory.

  4. Use the alternatives command to add a symbolic link to the Oracle JRE installation so that your system uses the Oracle JRE instead of the OpenJDK JRE:
    $ sudo alternatives --install /usr/bin/java java /usr/java/jre1.7.0_version/bin/java 200000
    If you have any problems, set the PATH and JAVA_HOME variables:
    export PATH="$PATH:/usr/java/latest/bin"
    set JAVA_HOME=/usr/java/latest
  5. Make sure your system is now using the correct JRE. For example:
    $ java -version
    java version "1.7.0_25"
    Java(TM) SE Runtime Environment (build 1.7.0_25-b15)
    Java HotSpot(TM) 64-Bit Server VM (build 23.25-b01, mixed mode)
  6. If the OpenJDK JRE is still being used, use the alternatives command to switch it. For example:
    $ sudo alternatives --config java
    There are 2 programs which provide java.
    
      Selection      Command
    ------------------------------------------------------------
       1             /usr/lib/jvm/jre-1.7.0-openjdk.x86_64/bin/java
    *+ 2             /usr/java/jre1.7.0_25/bin/java
    
    Enter to keep the current selection [+ ], or type selection number: 
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