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The PHD is no longer required and can be safely removed. If you have modified your Pentaho Hadoop Distribution installation you may wish to preserve these files so that the new Distributed Cache mechanism can take advantage of them. To do so follow the instructions hereabove: Customizing the Kettle Environment used by Pentaho MapReduce.
If you're using a version of the Pentaho Hadoop Distribution (PHD) that allows you to configure the installation directory via mapred-site.xml, preform the following on all TaskTracker nodes:
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