First of all, this book is meant to help you study for two different exams. This means that the topic are covered in a bit of a strange order. First, the RHCSA is covered. This is the Red Hat entry level exam. Unless you are a long time sysadmin, you can expect to learn quite a bit from this part of the book, even if you have been running Linux as a normal user for years (as I have). The second part is more focused, because the RHCE exam looks in more detail at various services and securing them. As a result of the author's decision to organize this way (which is helpful if you only want to study for one exam at a time and not dive in to the deep end), the book seems rather disjointed, You will end up studying topics like SELinux in one chapter, going totally away from it, and coming back to it a few chapters later. This makes it a substandard reference book, but as that isn't what it was meant for, I count the organization as a plus. It is more of a get your feet wet first, then dive in approach.
In terms of helping you study for the exam, some useful features include:
* Instructions for creating virtual machines to be used in the lab exercises.
* Bullet points summarizing each chapter.
* Exercises and (hands-on) labs for each chapter.
* As mentioned above, organization by test, so that you needn't worry about one if studying for the other.
Lastly, as with any topic you want to excel at, the key is to practice as much as you possibly can. To that end, you will want a machine with lots of disk space and perhaps a decent amount of rap which supports hardware virtualization, and preferably is running 64-bit Linux (which KVM on Red Hat seems to require). If you can't do this though, you probably want to set up dual booting to a few copies of Linux so that if you mess one up, you will still be able to use your machine. This won't be quite as satisfactory though, because messing up with fdisk or parted will still put you in a world of hurt (voice of experience here!), but with a VM, you will only mess up the VM and lose the time it takes to kickstart a new one. As far as the version of Linux, you will want to practice on either the official Red Hat Enterprise Linux, or one of the equivalent, freely available clones like CentOS (my choice) or Scientific Linux. If you try to use recent versions of Fedora, you will be a bit too cutting edge. I have found that it swaps out a lot of things (iptables, init, etc.) that RHEL is based on. Non-Red Hat versions are going to be quite a bit different too, and should probably be skipped, though a lot will still be similar.
It is worth mentioning that the Kindle edition seems to be some sort of PDF-like format which will not reflow to your screen. I can see the reason for doing this, but it would be nice if it was in standard Kindle format.
P.S. I should offer the disclaimer that I haven't yet taken either exam, so I can't sally how the book compares to the real thing, but even without passing the exam, this book has helped me greatly in my day-to-day dealings with LInux.
There is some decent content in here but it is undermined by the book's disorganization. The author frequently refers readers to other chapters and presents the reader with exercises or labs that require knowledge from future chapters. Remarkably little thought was put into the best order in which to cover topics and introduce concepts.
This is most aggravating in the early chapters where the reader is supposed to set up the practice environment they will use to run the exercises throughout the rest of the book. For example, Chapter 1 is, in theory, dedicated to helping the reader install the environment that will be used to practice throughout the rest of the book. Unfortunately, this environment requires the use of virtualization (through KVM), which is not covered until Chapter 2.
Also, ***if you buy the kindle version,*** it is important to know that there is no simple way to get the content that's on the CD including with the physical book. As that CD has the labs and practice tests, you're basically sunk without it. I had to contact customer service at McGraw Hill to get the content in the end.
So, that's a pretty negative review. Why two stars instead of one? At the end of the day, there are no good alternative guides for preparing for the RHCSA and RHCE. This book may only be marginally better than researching each test requirement online, but it's better than nothing.
As a preface, I've been a Unix admin for 15+ years on various systems: AIX, Solaris, Irix, HP-UX, DGUX, SCO, BSD, Linux, etc. so I have some perspective on this topic. Linux has been my personal OS for a long time, and with shifts in the job market I decided to pick up various Red Hat certifications to help the resume.
The good news: The book does present the raw materials you will need to know to pass the RHCSA and RHCE exams. In some places, the explanations are accurate.
The bad news: beyond the spaghetti logic of the book's organization noted by others, there's a degree of sloppy & inaccurate thinking I find troubling.
Some examples:
1) When discussing bash test operators, the author explains && (logical AND) as "asks if the preceding command is false" and || (logical OR) as "asks if the preceding command is true." This is horribly inaccurate: bash evaluates "A && B" as 0 (false) or 1 (true) based on the values of A and B. There is nothing "asking" anything. It is common in compiled and interpreted languages that an express such as A && B will "short circuit" -- when A is false, evaluation of the expression stops as it can never be true; B remains unprocessed as doing so would be a waste of cycles. Similar, an expression like A || B || C evaluates until one of the three is true, then execution short circuits again because the condition has been satisfied. While this may seem like splitting hairs, in the real world knowing the exact means by which systems, networks, etc. go about doing their work can be the difference between getting a promotion (or just keeping your job) and filing an unemployment claim.
2) When discussing configuration files, on more than one occasion the author writes "the configuration file configures the program." This is incorrect: a running program reads its configuration file and adjusts its run-time behavior to match stated directives. Implying a configuration file performs any action is analogous to stating the cart pushes the horse up a hill.
3) Several sections in the book begin "conceptually, this is what you do" -- this is inexcusable for a study guide to PRACTICAL exams. Red Hat does not ask you to take your best guess on multiple choice exams or described, in theory, how you would so something. Red Hat requires you to make it work on real systems.
4) There are numerous typos in example configuration files even AFTER the author stresses the importance of proper formatting and syntax! (Discuss of sendmail comes to mind immediately.)
5) In multiple places, the author writes paragraphs to pages detailing aspect of RHEL 5. The exams are about RHEL 6, not 5, and thus discussion RHEL5 is wasted space. "Upgrade" is not an exam objective, so knowing about RHEL5 is extraneous.
I give the book two stars because the author does provide numerous "Exam Notes" which little snippets of information about what to expect on the exam. In some cases, those notes are not things you would expect from reading the requirements. Overall, I strongly suggest you validate everything the author says both against man pages AND actual systems. There's just no sense from reading the book that the material's authoritative and accurate.
It is apparent that the author has a wealth of knowledge about the subject. I have been a Unix/Linux jock since 1995. It is a good thing I am or I would have never gotten past the first chapter. It is unfortunate that the initial start up of setting up a system to use for lab work is not documented in anything close to an understandable fashion. I believe the intention was to allow the user to think for themselves and to allow for personal choice in the distribution used while covering the 4 possible BROAD install scenarios. I think that the user of the book would be better served with a step by step base install at least to get an initial system configured in a way that the user would understand so that they could continue the book.
Maybe a simple disclaimer ....
These are the major distributions based on RHEL 6.X ( list1 list2 list3 ) coupled with 4 possible broad install types with many iterations. To achieve the goal of getting a base system configured for use in the following labs the installation that follows will be done using LIST1 to get the reader up and running. The various install options can be covered in depth during the labs in context.
The authors knowledge as stated is considerable and I am getting through it however it is VERY convoluted.After completing chapter one or so I thought, the questions asked bore no resemblance to anything I remembered actually performing. I went back through and reread the chapter with a highlighter looking for the answers. This is fine as it is a way of reviewing information that could not be covered by simply doing. All in all I am getting great value out of the book thus far even allowing for my considerable confusion getting started.
Product Details :
Paperback: 1072 pages
Publisher: McGraw-Hill Osborne Media; 6 edition (June 17, 2011)
Language: English
ISBN-10: 0071765654
ISBN-13: 978-0071765657
Product Dimensions: 7.3 x 2 x 9.1 inches
More Details about RHCSA/RHCE Red Hat Linux Certification Study Guide, Exams EX200 & EX300, 6th Edition, Certification Press
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