code: func (daemon *Daemon) reloadNetworkDiagnosticPort(conf *config.Config, attributes map[string]string) error {
  	if conf == nil || daemon.netController == nil || !conf.IsValueSet("network-diagnostic-port") ||
  		conf.NetworkDiagnosticPort < 1 || conf.NetworkDiagnosticPort > 65535 {
  		// If there is no config make sure that the diagnostic is off
  		if daemon.netController != nil {
  			daemon.netController.StopDiagnostic()
  		}
  		return nil
  	}
  	// Enable the network diagnostic if the flag is set with a valid port within the range
  	logrus.WithFields(logrus.Fields{"port": conf.NetworkDiagnosticPort, "ip": "127.0.0.1"}).Warn("Starting network diagnostic server")
  	daemon.netController.StartDiagnostic(conf.NetworkDiagnosticPort)
  
  	return nil
  }
docs: // reloadNetworkDiagnosticPort updates the network controller starting the diagnostic if the config is valid