ntop 실행했을때 에러메세지 좀 봐주세요

 ntop -d -w 3000 이렇게 명령을 입력하면

Wait please: ntop is coming up...
19/Sep/2003 09:37:59 ntop v.2.2 MT [i686-pc-linux-gnu] (09/19/03 09:30:44 AM build)
19/Sep/2003 09:37:59 Copyright 1998-2003 by Luca Deri <deri@ntop.org>
19/Sep/2003 09:37:59 Get the freshest ntop from http://www.ntop.org/
19/Sep/2003 09:37:59 Initializing ntop
19/Sep/2003 09:37:59 Initializing gdbm databases
19/Sep/2003 09:37:59 **FATAL_ERROR** ....open of /usr/local/var/ntop/addressQueue.db failed: File open error
19/Sep/2003 09:37:59 **FATAL_ERROR** Possible solution: please use '-P <directory>'

이렇게 메세지 뜹니다 명령어 사용법이 틀린건가요?