The city was known in the time of 11th-century geographer al-Bakri and, as he reported, was called Sidi Megdoul. In the 16th-century, a corruption of this name became known to the Portuguese as Mogador or Mogadore. The Berber and Arabic names mean the wall, a reference to the fortress walls that originally enclosed the city.
If the lobook is full, you can safely replace it. If the logbook has disappeared, I would be grateful for maintenance it, i.e. leaving a new logbook or even replacing the geocache. Just let us know in your log about it.