- The feature on which the subnetwork controller was enabled may not be reflected in the network topology. This means that it is dirty and has not been validated.
- Based on traversability from the starting point or points, no valid subnetwork controllers were found in the subnetwork. The Traversability section may include a condition barrier that is causing the trace to stop before reaching the subnetwork controller.
- There is a Trace rule configured to generate the diagram. Among the network elements in input for the diagram generation, there are devices that serve as subnetwork controllers and prevent the Trace rule from executing.
Ensure a valid subnetwork controller exists to be used in the trace. The feature that was enabled as a subnetwork controller must be validated to be reflected in the network topology.
Review the trace configuration to see whether changes are required, and attempt the trace again.
The diagram template related to the generated diagram must be reviewed. A Set Starting Point rule must be configured before the Trace rule to clearly specify the terminal or terminals that are expected as the starting points for the trace execution, and these terminals must be set as subnetwork controllers.