When switching from an all-in-one environment to a distributed environment, it may be desirable to have remote execution servers only.
How to uninstall the execution server (NES) from the server that also runs the management server (NAC).
1. stop the management server
2. delete the directory RA_HOME/webapps/execution and also the execution.war if present
3. restart the management server
If the agent is also running on the NAC server, you need to point it to a different NES as the local one is no more available. Refer to https://support.ca.com/us/knowledge-base-articles.TEC1694756.html for instructions on how to do that.