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The installation environment used by Pentaho MapReduce will be installed to pmr.kettle.dfs.install.dir/pmr.kettle.installation.id when the Pentaho MapReduce job entry is executed. If the installation already exists no modifications will be made and the job will use the environment as it existsis. That means any modifications after the initial run, or any custom pre-loading of a kettle environment, will be used as is by Pentaho MapReduce.
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