If you are a sys admin looking to secure a Linux system then this is certainly a book that deserves a slot on your bookshelf as it contains cutting edge information on how to keep a Linux system secure (as you would expect from ISECOM) and it will be extremely useful to you in this respect, but buy the earlier version if you are looking to learn how to hack Linux, as you will not learn any hacking methods from this book whatsoever. To be fair, the back cover does say you will learn about securing Linux and makes no mention of covering hacking topics.
My gripe is that it should not be sold under the Hacking Exposed brand name.
This has the wrong title I think, its basically what to do to prevent getting hacked, what configuration settings to apply and a lot of niche stuff you wouldn't really see much in the wild unless you have a spectrum analyser and you are going after a big corporate with very local access i.e.tempest issues. Hardly anything on tools as you get in normal hacking exposed books, very poor especially with the quality of the authors who have contributed, alot of old stuff i.e. telnet, finger, rhosts et al are still being used and these should be referenced as they are still stalwarts for getting access to a network, I think this book is coming from the wrong angle totally from every other one in the series I have read. There are a few new bits in there i.e. a little bit on web apps but these are generally glossed over. I am pleased I pre-ordered in feb and got this book for £15 but I'm not sure its worth that, alot of better books out there.