Here I provide a minimal example using Fast-RTPS client-server discovery that hope suit your needs:
ros2 client-server minimal example
To summarize, we introduce a fleet of two robots. Each robot has a sensor, actuator, and control nodes. The control node manages local behavior and receives commands from a fleet manager node.
In order to minimize network traffic, we want the sensor and actuator topics to be restricted to the robots. That is only sensors, actuators, and local control exchange this type of message.
On the other hand, we want local control nodes to exchange command topics among them and the fleet server but never with sensors or actuators.