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.
- Administering Users and Clusters
  Lists topics that help manage a MapR cluster.
- Administering Nodes
  Provides a synopsis of managing nodes in a cluster.
- Administering Volumes
  This section provide information about how to organize and manage data using volumes, a unique feature of MapR clusters.
- Administering Files and Directories
- Administering Tables
  Administration of the MapR Database is done primarily via the command line (maprcli) or with the Managed Control System (MCS). Regardless of whether the MapR Database table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter options. MapR Database administration is associated with tables, columns and column families, and table regions.
- Administering Streams
- Administering MapR Gateways
  A MapR gateway mediates one-way communication between a source MapR cluster and a destination cluster. You can replicate MapR Database tables (binary and JSON) and MapR Event Store For Apache Kafka streams. MapR gateways also apply updates from JSON tables to their secondary indexes and propagate Change Data Capture (CDC) logs.
- Administering Services
- Monitoring the Cluster
  This section describes how to monitor the health and performance of a MapR cluster.
- Configuring Security
  Describes how to configure security and manage secure clusters.
- Managing Secure Clusters
  Provides procedures that will enable you to use MapR clusters securely.
- Administering the MapR Data Access Gateway
  The MapR Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight client applications and the MapR cluster. This section describes considerations when upgrading the service, how to modify configuration settings, and how to administer and manage the service.
- Planning for High Availability
- Administrator's Reference
  This section contains in-depth reference information for the administrator.
  - maprcli and REST API Syntax
    This section provides information about the MapR command API. Most commands can be run on the command-line interface (CLI), or by making REST requests programmatically or in a browser.
    - Overview
      Each command reference page includes the command syntax, a table that describes the parameters, and examples of command usage.
    - acerole validate
      Verifies given user roles for ACEs exists in the /opt/mapr/conf/m7_permissions_roles_refimpl.conf file.
    - acl
      Describes the acl commands used to access control lists (ACLs).
    - alarm
      Describes the alarm commands that perform functions related to system alarms.
    - audit
      Describes commands used to audit operations related to cluster management and data access.
    - blacklist
      Describes commands used to blacklist and to list blacklisted users.
    - cluster
      Manages cluster features, gateways, and cluster-wide settings.
    - config
      Lists configuration values for the MapR cluster.
    - dashboard info
      Displays a summary of information about the cluster.
    - dialhome
    - disk
      Lists disk parameters.
    - dump
      Returns key information about volumes, containers, storage pools, and MapR cluster services for debugging and troubleshooting.
    - entity
      Manages entities (users and groups).
    - fid
      Displays information about MapR Database or file-system components that are identified by a FID.
    - file
      Lets you perform tiering operations at the file level.
    - job
      Manages Hadoop jobs running on the cluster.
    - license
      Manages MapR licenses.
    - nfsmgmt
      Refreshes NFS exports and server cache.
    - nfs4mgmt
      Manages NFSv4 server.
    - node
      Manages nodes in the cluster
    - rlimit
      Manages resource usage limits for the cluster.
    - schedule
      Manages schedules.
    - security
    - service list
      Lists all services on the specified node, the memory allocated for each service, the state of each service, and log path for each service.
    - setloglevel
      Sets log level on individual services.
    - stream
      Manages stream functionality.
    - table
      Performs functions related to MapR Database tables.
    - tier
      Lets you create, modify, remove, and retrieve list of tiers and tiering rules.
    - trace
      Lets you view and modify the trace buffer, and the trace levels for the system modules.
      - trace dump
        Dumps the contents of the trace buffer into the MapR file system log.
      - trace info
        Displays the trace level of each module.
      - trace print
        Manually dumps the trace buffer to stdout.
      - trace reset
        Resets the in-memory trace buffer.
      - trace resize
        Resizes the trace buffer.
      - trace setlevel
        Sets the trace level on one or more modules.
      - trace setmode
        Sets the trace mode.
    - urls
      Displays the status page URL for the specified service.
    - virtualip
      Manages virtual IP addresses for NFS nodes.
    - volume
      Manages volumes, snapshots and mirrors.
  - Utilities
    Contains information about various scripts and utilities, that help setup, maintain, and monitor clusters.
  - Configuration Files
    This section contains reference information about various configuration files.
  - Alarms Reference
    The pages in this section provide details about all of the types of alarms.
  - MapR Data Platform Environment
    This section provides information associated with the MapR Data Platform environment.
  - Sample JSON File for Metering
    A sample metering JSON file for an 8-node cluster with no workloads enabled.
  - Metering Data Descriptions
    This table lists the metrics collected by the metering feature.
- Troubleshooting Cluster Administration
  Lists the common errors and their solutions.
- Best Practices for Backing Up MapR Information
  Lists the best practices and performance considerations to follow when backing up MapR information.
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.
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.

trace print

Manually dumps the trace buffer to stdout.

Syntax

CLI

maprcli trace print
    [ -host <host> ]
    [ -port <port> ]
    -size <size>

REST

None.

Parameters

Parameter	Description
host	The IP address of the node from which to dump the trace buffer to stdout. Default: `localhost`
port	The port to use. Default: `5660`
size	The number of kilobytes of the trace buffer to print. Maximum: 64

Output

The most recent <size> bytes of the trace buffer.

-----------------------------------------------------
2010-10-04 13:59:31,0000 Program: mfs on Host: fakehost IP: 0.0.0.0, Port: 0, PID: 0

-----------------------------------------------------
DONE

Examples

Display the trace buffer:

CLI

maprcli trace print