I have finished exercise 8.6, but after completing, the state_result returned is = 3 (WARN) even though the action works as expected. Referencing the ROS docs, it looks like the GoalStatus message 3 actually means SUCCEEDED. Does that mean there is an error in the example, and 3 should = SUCCESS, not WARN?
I can’t be sure unless I see your code, but it’s possible that the state_result 3 was redefined as WARN somewhere in your code.
Can you show us the output of your exercise and maybe the code also?