When starting CloudBees CD (CloudBees Flow) server/agent, it’s possible that you meet an error (in commander-service.log) like the following one:
STATUS | wrapper | 2017/10/06 14:12:47.398 | Launching a JVM... INFO | jvm 1 | 2017/10/06 14:12:47.699 | WrapperManager: Initializing... INFO | jvm 1 | 2017/10/06 14:12:48.800 | WrapperManager Error: Failed to connect to the Wrapper at port 32,000. Cause: java.net.ConnectException: Connection refused (Connection refused) INFO | jvm 1 | 2017/10/06 14:12:48.800 | WrapperManager Error: Exiting JVM... ERROR | wrapper | 2017/10/06 14:12:49.251 | JVM exited while loading the application.
This error tells that the JVM is not able to connect to the Java Service Wrapper. This is probably caused by port conflicts (in the above case, port 32000) in the machine (port is used by other applications).
We can configure the port that the Java Service Wrapper uses in the file wrapper.conf with following properties:
wrapper.port=0 wrapper.port.min=32000 wrapper.port.max=32999
Please refer to the following page to get more details: