After reading this book, I think it is going to be the mandatory companion I hand out to new Linux administrators, along with Essential System Administration. The first 6 chapters are exceptional.  I can't say enough good things about them.  The coverage of PAM is better than anything I have seen.  The coverage of authentication, groups, users and best practices surrounding them was very good as well.  The logging chapter alone is probably worth the purchase of the book. After the first section, the book covers more specific topics that are of less interest to me.  I realize that a lot of people use email, of all kinds.  Chapter 7, 8 and 9 cover email, and I just wasn't that excited about it. Chapter 10 covered securing FTP, which is nice, and 11 covers Bind.  I guess I wonder why some of the topics were chosen.  There are whole books on email and bind, available, but there isn't always good material for some other services, like CUPS, maybe some web-based administration tools, or SELinux.  The coverage of topics that made the table of contents are very good. I would say if you are new to Linux Security, or a seasoned player looking for just another reference, this book is great.

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