Comment by li9i for Make sure you have set in navfn_global_planner_params.yaml:allow_unknown: false #Specifies whether or not to allow navfn to create plans that traverse unknown space, default true I have observed that sometimes the first plan (after setting a goal) can still be wrong, but then it gets updated by the next plan (which is correct). If the planner frequency is high enough, then the robot does not have a chance to do anything undesirable.Also, from:https://answers.ros.org/question/2155...Are you using a layered costmap from costmap_2d with an obstacle or voxel layer? If so you have to set the param track_unknown_space for that layer to true, otherwise it's converting your map's unknown space into free space (which navfn then correctly goes quite happily through).So, make sure you have also set in costmap_common_params.yaml: track_unknown_space: true #true needed for disabling global path planning through unknown space

I was also frustrated with this issue. For future reference see https://github.com/ros-planning/navigation/issues/261#issuecomment-885545451