This stack upgrade involves removing the HDP 1.x version of MapReduce and replacing it
with the HDP 2.x YARN and MapReduce2 components. This process is somewhat long and
complex. To help you, a Python script is provided to automate some of the upgrade steps.
It is available at
/var/lib/ambari-server/resources/scripts/UpgradeHelper_HDP2.py
on the Ambari Server host. The script can be executed on any host that can communicate
with Ambari Server. It requires Python 2.6 or higher.