In this article Scott McMahan reviews a few Linux related books. One of the books included was Linux System Security. Here is what he had to say... I could stop with a one-word review, because that’s all Linux System Security requires: it is the only book I’ve ever seen that discusses Linux security administration, hitherto an obscure area learned informally from word-of-mouth and experimentation. If you need to learn how to implement Linux security, this is it! I can’t recommend this book highly enough for those who need to learn Linux security from scratch.