I tried modifying the 'storm.scheduler' setting in /etc/storm/conf/storm.yaml because I need the resource aware scheduler (http://storm.apache.org/releases/current/Resource_Aware_Scheduler_overview.html) so that I can dedicate cores for executors.
I have two nimbuses and one supervisor and three zookeeper. I made the changes to the storm yaml file on the nimbus and supervisor machines. After I restart all components I checked all the storm yaml files but they no longer have my changes. This setting cannot be found listed in the Ambari UI so I cannot use the UI to address the issue.
This is an Ambari "feature". Every time you restart the service Ambari overrides the configuration with the configuration defined in Ambari.
To enable RAS you should go to Storm / Configuration / Custom storm-site then click on "Add property ...".
Then you'll be able to add your desired RAS setting:
After setting the param you should restart all the Storm services.