HPE Ezmeral Data Fabric 6.1.x is In Maintenance and transitions to "End of Maintenance" in June 2024. Please see the latest documentation.

About MapR 6.1
This site contains the main documentation for Version 6.1 of the MapR Converged Data Platform, including installation, configuration, administration, and reference information.
6.1 Installation
This section contains information about installing and upgrading MapR software. It also contains information about how to migrate data and applications from an Apache Hadoop cluster to a MapR cluster.
6.1 MapR Data Platform
MapR Data Platform is the industry-leading data platform for AI and analytics that solves enterprise business needs.
6.1 Administration
This section describes how to manage the nodes and services that make up a cluster.
6.1 Development
This section contains information related to application development for Ezmeral ecosystem components and MapR Data Platform products, including the file system, Database (Key-Value and JSON), and Event Streams.
- Application Development Process
  Before you start developing applications on the MapR Data Platform platform, consider how you will get the data into the platform, the storage format of the data, the type of processing or modeling that is required, and how the data will be accessed.
- MapR XD and Apps
  The following sections provide information about accessing the MapR XD with C and Java applications.
- MapR Database and Apps
  This section contains information about developing client applications for JSON and key-value tables.
- MapR Event Store For Apache Kafka and Apps
  MapR Event Store For Apache Kafka brings integrated publish and subscribe messaging to MapR Data Platform.
- MapReduce and Apps
  This section contains information associated with developing YARN applications.
- MapR Data Science Refinery
  The MapR Data Science Refinery product is an easy-to-deploy and scalable data science toolkit with native access to all platform assets and superior out-of-the-box security.
- MapR Data Fabric for Kubernetes
  This section describes how to leverage the capabilities of the MapR Data Fabric for Kubernetes.
- Ecosystem Components
  The following sections provide information about each open-source project that is supported by the MapR Data Platform.
- Maven and MapR
  This section discusses topics associated with Maven and MapR.
- Developer's Reference
  This section contains in-depth information for the developer.
  - MapR Database Shell (JSON Tables)
    The mapr dbshell is a tool that enables you to create and perform basic manipulation of JSON tables and documents. You run dbshell by typing mapr dbshell on the command line after logging into a node in a MapR Data Platform cluster.
  - Utilities for MapR Database JSON Tables
    MapR Database JSON provides utilities to copy, export, and import data, compare table content, and verify the consistency of secondary indexes.
  - MapR Database HBase Shell (Binary Tables)
    You can manage MapR Database tables using HBase shell commands and additional HBase shell commands included in the MapR Data Platform distribution of Hadoop.
  - Utilities for MapR Database Binary Tables
    MapR Database provides utilities to copy and compare data in MapR Database binary tables.
  - MapR Event Store For Apache Kafka Utilities
  - YARN Commands
    This section describes the YARN commands.
    - yarn application
      The yarn application lists applications, or prints the status or kills the specified application.
    - yarn classpath
    - yarn daemonlog
    - yarn debugcontrol
      used to save additional DEBUG logs for scheduling in YARN to a separate file without restarting the RM.
    - yarn jar
    - yarn logs
      Dumps the YARN container logs.
    - yarn node
    - yarn queue
    - yarn rmadmin
    - yarn version
  - Source Code for MapR Software
    MapR releases source code to the open-source community for enhancements that HPE has made to the Apache Hadoop project and other ecosystem components.
  - Hadoop Commands
    This section describes the Hadoop commands.
- API Documentation
  MapR Data Platform supports public APIs for MapR File System, MapR Database, and MapR Event Store For Apache Kafka. These APIs are available for application-development purposes.
Other Docs
This section contains release-independent information, including: MapR Installer documentation, Ecosystem release notes, interoperability matrices, security vulnerabilities, and links to other MapR version documentation.
Glossary
Definitions for commonly used terms in MapR Converged Data Platform environments.

yarn debugcontrol

used to save additional DEBUG logs for scheduling in YARN to a separate file without restarting the RM.

The logs are saved in /opt/mapr/Hadoop/Hadoop<version>/logs/yarn-mapr-scheduling-debug.log

Syntax

yarn debugcontrol

Parameters

Parameter	Description
-addapp <application_name>	enables additional scheduling DEBUG on the application
-addqueue <queue_name>	enables additional scheduling DEBUG on the queue
-removeapp <application_name>	disable addition scheduling DEBUG on the application
-removequeue <queue_name>	disable addition scheduling DEBUG on the queue
-getapps	lists the applications with additional scheduling DEBUG
-getqueues	lists the queues with additional scheduling DEBUG