Software

In order to run MapR software and Hadoop, you must install certain software on your node.

Java

MapR core requires the Java Development Kit (JDK). Installing only the Java runtime environment (JRE) is not sufficient. Verify that one of the following JDK versions is installed on the node:

Java Requirements for MapR Core
  • Sun Java JDK 1.7 or 1.8
  • OpenJDK 1.7 or 1.8
Note: Make sure you have the development kit installed. Some JRE packages include jdk in the name, but do not provide the required JDK software.
Special Requirements for Using OpenJDK

If you use OpenJDK:

  • RedHat/CentOS must have java-<version>-openjdk-devel installed.
  • SUSE nodes must have java-<version>-openjdk-devel installed.
  • Ubuntu nodes must have openjdk-<version>-jdk installed.
Note: The openjdk-devel package and openjdk-7-jdk package include the jps command that lists running Java processes and can show whether the CLDB has started. This command is not supported in the Sun Java JRE.
To install the Oracle/Sun Java JDK:
Obtain the Oracle/Sun Java Development Kit (JDK), available at Oracle's Java SE website. Find Java SE 7 in the archive of previous versions.
To install or update OpenJDK
Use a package manager, such as yum (RedHat, Oracle Linux, or CentOS), apt-get (Ubuntu) or zypper (SUSE).
  • On RedHat, Oracle Linux, or CentOS:
    # yum install java-1.7.0-openjdk-devel
  • On Ubuntu:
    # apt-get install openjdk-7-jdk
  • SUSE
    # zypper install java-1_7_0-openjdk-devel

MySQL

The MapR Metrics service, which provides metrics for MapReduce (MRv1), requires access to a MySQL server running version 5.1 or later. MySQL does not have to be installed on a node in the cluster, but it must be on the same network as the cluster. If you do not plan to use MapR Metrics, MySQL is not required.