Coloring nodes

[Lithimlin]

Is there a way to color nodes in the gui? I want to color sub-groups created by a router to check its correct implementation.
Alternatively, what is the recommended way to check whether an implementation is correct?

Unit tests seem a bit too complicated as I'd have to access a host's interfaces as well and don't really know where I would have to start with that.

[akeranen]

You would have to change the source code to do that. Unit tests are highly encouraged since they can be used also later to ensure further improvements don’t break existing functionality.