Besides a Linux Administration book, will this course be a good as 'only resource' to pass the SysAdmin exam?
I'm not sure what you are asking. If you are inquiring if just taking this course is adequate preparation for the LFCS exam, the answer is no for most people. This course will help prepare you for the exam, but it is definitely not an "exam prep" course. You need to make use of the other resources talked about on the certification page.