This is documentation for MapR Version 5.0. You can also refer to MapR documentation for the latest release.

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Code Block
root@testnode100:/opt/mapr/conf/conf.d# hadoop2 conf | grep mapreduce.map.memory.mb
<property><name>mapreduce.map.memory.mb</name><value>1024</value></property>

root@testnode100:/opt/mapr/conf/conf.d# hadoop -yarn conf | grep mapreduce.map.memory.mb
<property><name>mapreduce.map.memory.mb</name><value>1024</value></property>

Syntax Summary

The following syntax summary applies to all commands.:

Syntax Summary

No Format
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hadoop [-yarn|-classic] [--config confdir] [COMMAND] [GENERIC_OPTIONS] [COMMAND_OPTIONS]
 
hadoop1 [--config confdir] [COMMAND] [GENERIC_OPTIONS] [COMMAND_OPTIONS]
 
hadoop2 [--config confdir] [COMMAND] [GENERIC_OPTIONS] [COMMAND_OPTIONS]

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COMMAND_OPTION

Description

-mode

Specifies the Hadoop version: yarn or classic

Aternatively, you can use a hadoop1 or hadoop2 command without setting the mode.

If you use a hadoop command (instead of hadoop1 or hadoop2) and do not set the mode, the command runs in the mode set by the MAPR_MAPREDUCE_MODE environment variable.

If this variable is not set, the command runs in the mode set in the hadoop version file on the node (default_mode = yarn or classic).

--config confdir

Overwrites the default Configuration directory. Default is ${HADOOP_HOME}/conf.

COMMAND

Various commands with their options are described in the following sections.

GENERIC_OPTIONS

The common set of options supported by multiple commands.

COMMAND_OPTIONS

Various command options are described in the following sections.

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Unsupported Commands

MapR does not support the following Hadoop commands:

  • balancer

  • datanode

  • dfsadmin

  • fsck

  • fetchdt

  • jobtracker
  • namenode 

  • secondarynamenode

  • tasktracker

Generic Options

Implement the Tool interface to make the following command-line options available for many of the Hadoop commands.

Generic The following generic options are supported by the distcp, fs, job, mradmin, pipes, and queue Hadoop commands.:

Generic Option

Description

-conf <filename1 filename2 ...>

Add the specified configuration files to the list of resources available in the configuration.

-D <property=value>

Set a value for the specified Hadoop configuration property.

-fs <local|filesystem URI>

Set the URI of the default filesystem.

-jt <local|jobtracker:port>

Specify a jobtracker for a given host and port. This command option is a shortcut for -D mapred.job.tracker=host:port

-files <file1,file2,...>

Specify files to be copied to the map reduce cluster.

-libjars <jar1,jar2,...>

Specify JAR files to be included in the classpath of the mapper and reducer tasks.

-archives <archive1,archive2,...>

Specify archive files (JAR, tar, tar.gz, ZIP) to be copied and unarchived on the task node.