For Ambari 1.6.0, make the template modification on Ambari Server /var/lib/ambari-server/resources/stacks/HDP/2.0.6/hooks/before-START/templates/hadoop-env.sh.j2
Make mods to this file only on the Ambari Server and it will get re-distributed to the agents after you do Ambari Server restart. You don’t need to edit files on the agents. And you don’t need to edit any of the puppet files any longer. They are not being used (as of Ambari 1.5.0).
But also you’ll find log4.properties is now available from the UI and REST API to modify for each Service. Log into Ambari Web and browse to Services > HDFS > Configs. Scroll down and you’ll see the log4.properties section. You can modify that file there and it will be distributed with the configs.