gistfile1.txt

  map.resources :settings
  map.namespace(:settings) do |setting| 
    setting.resources :units
    setting.resources :groups
  end

class Settings::Units < SettingsController
end
class Settings::Groups < SettingsController
end

link_to 'Groups', settings_groups_path
--> which leads to SettingsController.show, though i expected: Groups.index