UBUNTU root 密码 : http://www.google.com/search?hl=en&newwindow=1&client=firefox-a&rls=com.ubuntu%3Azh-CN%3Aunofficial&hs=Vi1&q=UBUNTU+root%E5%AF%86%E7%A0%81&btnG=Search&lr=lang_zh-CN|lang_en