exit code 127 means that the system could not find the requested executable (could be /bin/nohup, /opt/java/bin/java or the sonar-application.jar). can you validate that the pathes in your service description are correct and sonarqube is starting when you run the parameters of ExecStart ...
It looks like backstage is unable to find/parse the port section of your config. I tried to reproduce this locally and get errors if I set a too high port numer or true/false as port but I have managed to getReceived NaNso something is probably wrong with the configuration file. I'd ...