Red Hat Enterprise Linux 9: Exam Guide EX200

I am delighted to provide a very positive review for the RHCSA Red Hat Enterprise Linux 9: Training and Exam Preparation Guide (EX200), Third Edition. This book is an exceptional resource for anyone seeking to become a Red Hat Certified System Administrator (RHCSA) and excel in the field of enterprise Linux system administration.

The author, Asghar Ghori, has done a fantastic job of breaking down complex concepts into easily understandable language. The book is well-structured and covers all the necessary topics in a logical order, making it easy to follow along and comprehend. The exercises and practical examples provided throughout the book are also helpful in reinforcing concepts and applying them to real-world scenarios.

One of the things I appreciated most about this book is its comprehensive coverage of Red Hat Enterprise Linux 9. The author has ensured that all the relevant topics for the RHCSA exam are covered in-depth, from installation and configuration to system administration, networking, and security. This comprehensive coverage makes it an invaluable resource for not just passing the exam but also for becoming an expert in the field.

Furthermore, the book includes a wide range of practice questions and exam simulations, which are incredibly helpful in preparing for the RHCSA exam. The author has done an excellent job of mimicking the format and difficulty level of the actual exam, so readers can feel confident in their preparedness.

In summary, the RHCSA Red Hat Enterprise Linux 9: Training and Exam Preparation Guide (EX200), Third Edition, is a must-read for anyone seeking to become a Red Hat Certified System Administrator. It is a well-written, comprehensive, and practical resource that covers all the necessary topics and provides ample opportunities for practice and preparation. I highly recommend this book to anyone interested in pursuing a career in Linux system administration.

I’m completely new to RHEL and so far I haven’t really made it past the first chapter because this book isn’t really good. The explanations in the first chapter are not working and I’m doing exactly what the book says. I figured something’s out on my own and on YouTube. But keep your money, he’s not a good author

…watch out for typos and problems with some of the explanations in some parts of the book.

I bought this book (kindle version) and used it to pass the RHCSA. The book is clearly tailored for the RHCSA and to be fair does live up to that reputation. There are a lot of exercises and examples that clearly outline what the author is trying to convey. Examples are clear to understand and if you do the exercises yourself, then you are well on your way to passing the RHCSA.

However, there are a lot of typos big and small and I did send them to the author with the assumption that it would benefit others with the corrections (especially the kindle version). The author was responsive at the beginning acknowledging the errors. I did not check whether they have been fixed or not. I just went through the content after making note of the typos and with the understanding that he would fix it.

The topics are well covered and explained. Three topics that could have been better covered are SELinux, AutoFS and Containers. The explanation uses excessive word-o-logy that leaves somebody new to SELinux with tons of confusion and more questions. I used youtube resources to prep myself on the how and why (Ed Walsh on a youtube channel clearly explains the need for SELinux – I have not seen a better explanation than Ed’s anywhere else). The author’s coverage of AutoFS is again excessive word-o-logy that is a confusing mess. The examples are fine, but the explanation uses confusing rhetoric that can leave you messed up with NFS and AutoFS setup. I read explanations on direct and indirect mappings and watched a couple of youtube videos before I understood what the author was trying to convey. I pointed out both of these to the author.

The container chapter is missing explanations or examples that the reader is well advised to take note. DIY labs 22-3 and 22-4 relate to rootless containers and therefore has to be launched as a regular user. Both labs require that you launch rootless, persistent data containers with folders under /. However, the author does not mention in any of his examples that this type of container requires you to “chown” the folders under root to belong to the user. If you launch a rootless container with this setup as a regular user without “chown”ing, (even with full DAC permissions for everybody) then SELinux does not want to apply the correct context type (container_t to the shared folder). For both these DIYs, if you make a folder anywhere other than areas that a regular user can write or has access, then you will need to “chown” it to the user before launching the rootless container, otherwise this has to be launched as a root container not rootless. I pointed this out to the author. I did not hear from him. Further, container questions (20,21,22) in mock exam #3 has user60 with a NFS mounted home folder. The questions relate to launching rootless containers as user60 with a NFS mounted home folder. SELinux barfs when it encounters the home folder with a type context as “nfs_t” for user60. It suggests workarounds that did not work for me. I googled it and the latest versions of podman seem to have some fix for the errors associated with a home folder on a NFS server. I tried to research this issue further but had an exam scheduled within days. Therefore, I requested the author for clarification/help. Here again, I did not hear from him. Luckily, I did not have to work on any such scenarios on the real test.

Still, the book is a good reference to the topics on the test and is pretty useful. Although I had to refer to other resources for some chapters, the examples and mock exams are very good.