move_base not updating path

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When costmap occures in robot global path due to local obstacles, mvoe base is only updating the global pth after it goes very near to the obstacle and finds out that its is near obstacle. Is it possible to make move_base update the global path whenever the global plan is invalid due to presenece of costmap it the global path? If now how to make the move base do it externally? I found out tht their is a service called /make_plan in move_base it looks like this service call will only return new global path to the goal but don't update the global path, how to do so? I am using navfn for global path planning.