A system and method automatically configures the interfaces of an intermediate network device. A discovery process operating at the device detects the identity or type of network entities actually coupled to the device's interfaces. Utilizing the identity or type of detected entities, a look-up is performed to obtain a configuration macro specially defined for each detected network entity. The retrieved configuration macros are executed and applied at the respective interfaces. During operation, the intermediate network device continues to monitor the identity and type of entities actually coupled to its interfaces. If a change is detected, such as an entity moving from a first to a second interface, the specially defined configuration macro for that entity floats from the first to the second interface where it is executed and applied.