According to the Cisco AppDynamics Professional Implementer (CAPI) documents, when updating the Database Agent, you need to follow these steps12:
Stop the agent as described for your specific installation in Start and Stop the Database Agent.
Make a copy of the existing agent directory, . Backing up allows you to revert to the previous agent installation if you need to. You can also copy over the controller-info.xml configuration file to the new installation to ensure the agent configuration is maintained.
Install the Database Agent as described for your specific installation in Administer the Database Agent.
Copy the \conf\controller-info.xml file to the new installation directory, \conf. To ensure the agent configuration is maintained, copy the \conf\controller-info.xml file to the new installation directory, \conf.
Start the new agent. See Start and Stop the Database Agent.
Verify the Database Agent Installation. See Verify the Database Agent Installation.
Therefore, the correct statements are:
The Database Agent must be stopped and restarted during the upgrade. (A)
Controller-info.xml is the only file that needs to be migrated from the previous agent to the new agent. (D)
The incorrect statements are:
If the agent is moved to a new location during the upgrade, the AppDynamics Controller must be reconfigured to reference the new location of the agent. (B) This is not true because the controller-info.xml file contains the information about the Controller host, port, account name, access key, and SSL settings. As long as this file is copied to the new agent location, the Controller does not need to be reconfigured.
All data collectors created from the previous agent must be migrated to the new agent. © This is not true because the data collectors are configured on the Controller UI, not on the agent. The agent collects the metrics from the databases and sends them to the Controller. The data collectors do not need to be migrated to the new agent.
After the Database Agent is upgraded, the AppDynamics Controller must be restarted. (E) This is not true because the Controller does not depend on the agent version. The agent and the Controller are compatible as long as they meet the Agent and Controller Compatibility requirements.
References:
1: Upgrade the Database Agent - AppDynamics
2: Release Upgrade Checklist for Database Agents - AppDynamics
