#appdynamics db agent Connection issue with controller using DB agent

[indhumathys]

• Im using Java 8
  java version "1.8.0_202"
  Java(TM) SE Runtime Environment (build 1.8.0_202-b08)
  Java HotSpot(TM) Client VM (build 25.202-b08, mixed mode)

• Downloaded DB agent from the Controller and extraced,
  while starting the DB agent it throws exception: Could not connect to the controller/invalid response from controller

• Error Message
  ] ControllerHttpRequestResponse:25 - Fatal transport error while connecting to URL [/controller/instance/UNKNOWN_MACHINE_ID/systemagentregistration]: org.apache.http.NoHttpResponseException: grace202504080038013.saas.appdynamics.com:443 failed to respond
  10 Apr 2025 10:10:52,716 WARN [DBAgent-1] RegistrationChannel:128 - Could not connect to the controller/invalid response from controller, cannot get registration information

[livehybrid]

Hi @indhumathys 

The error indicates the DB agent cannot establish a connection with the AppDynamics Controller, likely due to network issues, incorrect configuration, or SSL/TLS problems.

• Verify the Controller URL and port in controller-info.xml or startup parameters are correct (grace202504080038013.saas.appdynamics.com:443).
• Ensure the Controller is reachable from the DB agent host (test with telnet or curl). e.g. 

curl -v https://grace202504080038013.saas.appdynamics.com​

• Check if your Java version supports the required TLS version (Java 8u202 supports TLS 1.2 by default).
• Validate the account name, access key, and application name in the agent configuration.
• If using a proxy, ensure proxy settings are correctly configured.

Check out the following docs for more info: https://docs.appdynamics.com/appd/24.x/latest/en/database-visibility/administer-the-database-agent/i...

🌟 Did this answer help you? If so, please consider:

• Adding karma to show it was useful
• Marking it as the solution if it resolved your issue
• Commenting if you need any clarification

Your feedback encourages the volunteers in this community to continue contributing