Passing Red Hat’s RHCSA certification (EX200): my experience

Just a week ago I passed the Red Hat Certified System Administrator exam, and here are some brief notes about my experience.

Why the RHCSA certification?

At first I didn’t plan on taking the exam at all. But I have been using pretty much Debian/Xubuntu only for a long long time and for the last two years I have been managing RHEL based machines. And I knew nothing about that world.

After taking the exam and passing it this is why, in my opinion, the certification is worth its price:

First things first, even though it’s not explicitly stated you are supposed to know the basic of GNU/Linux to a high level of details. For me an example of this was file and directory permissions. I have always known good ol’ -rwxrwxrwx and quite frankly I’ve gone reasonably far with that, but the studying has forced me to learn all of the details of permissions: all the various control bits (setuid, setgid, sticky), access control lists (ACLs) and extended attributes (getattr/setattr). Some things make a lot more sense to me now that I have formalized the meaning of it all.

SELinux was a marvel that I want to learn more about. Put simply, SELinux is the definitive way of saying “this application can do this and that, and nothing more” and have it actually enforced.

Another thing: I had to learn how to use systemd. Absolutely worth it. Quite frankly, now that I understand it, it’s not that bad. It’s quite good, actually. I like the consistency across many aspect of system management that systemd brings to the GNU/Linux world.

The last thing: the exam is performance based. There’s no escape from this: either you have learned how to manage a RHEL system to a certain degree of detail, or you won’t pass. This is in contrast to some other certifications that are question-based (with multiple answers). There are many approaches to this kind of exams, and some people will just go ahead and cheat. As some people told me, it’s feasible (and many people do it). This is basically not possible at an RHCSA Exam (and this is particularly true if, like me, you take the exam in Kiosk mode — more on that later).

Long story short: if you reach a passing level, you actually have those competencies, and have enough competencies to learn the missing bits (for example some advanced SELinux features that are not needed for the exam but that may come handy in real life).

Learning materials

I have a paid LinuxAcademy account and quite frankly, it’s worth every cent of its cost. I plan on keeping my account and renewing my subscription.

Beside that, I also got a copy of Ghori’s book about RHEL7 RHCSA&RHCE certifications. This book is a bit meh, but since the copy I read has been lent to me by a colleague, it was worth reading.

Another resource was CertDepot’s RHEL7 section. Quite frankly, I did not make use of that content at the time I discovered it (I was ahead enough in the study I had no real need for that content).

I have used a real, (not so much) old computer. This was crucial to my passing the exam. It was a Dell Optiplex 780. Nothing special here: 6GB ram, 160GB hard rotational disk, an Intel Core 2 Duo E8400 CPU. A slow computer that did the job. I tested pretty much all of the likely to happen tasks and some more on this machine. Getting openvpn to run on it was particularly interesting as I got experience in dealing with systemd units since this is an unusual service (from the exam preparation point of view).

Last but not the least, one of the most-worth pieces of learning material was this post from Finnbarr P. Murphy: So you think you’re ready for the RHCSA Exam. This was eye-opening because it let me test my knowledge against somebody else opinion. That was my my metering of knowledge. That was somebody else’s metering of knowledge. The challenges were non-obvious and I failed and found myself in a dead end in many occasions. I went back to study materials after every task I could not do, and did the challenges over and over again until I could do all the tasks from start to finish without any doubt.

How much did it take to prepare?

Well first you should understand that I was studying this content while juggling with a full-time job, some university courses and some social life (my SO mostly).

That being said, I studied on-and-off for roughly six months. When I say on-and-off i mean that I had like a whole month pause because I had other stuff to do.

After taking out pauses, I could probably have condensed it in three months, probably something less if I had not over-studied it.

The Exam

In retrospect, LinuxAcademy’s content was enough and my approach definitely was an overkill. ButI passed the exam and I got 300/300 (even though this does not appear of the certificate). Still a satisfaction, though.

Speaking about my examination experience, I have to first preface that I took the exam in Kiosk mode. That is, I was in a test center alone in a room, using only a test-center-provided laptop and there was a Red Hat proctor looking at me via two (not one) webcams.

The laptop was a ThinkPad P71 (worth noting despite not being relevant or useful, lol). The laptop webcam was pointed at me. The second, usb-connected webcam was needed so that I could take it in my hand and show the proctor the whole room around me. I had to prove that the whole room was empty, that there was nothing on the walls in front of me, at my sides and behind me. I also had to show the roof of the room and show what was below the desk i was using. I was not allowed to even have my watch (understandable). The proctor had video feedback but no audio feedback. I was instructed not to read tasks aloud as this would have triggered the proctor because he/she might think I was reading the question to someone else. Understandable and not a big deal.

Basically, I had to prove I was alone and I could only rely on my knowledge and experience to pass the exam. Super fair. I liked that.

Regarding the exam tasks… The tasks were absolutely reasonable. I cannot say more because of the NDA. But i found them to be just reasonable.

What next?

The next step in the Red Hat ladder is the Red Hat Certified Engineer exam. I had to give back the Ghori book but I am studying some content anyway.

I am not 100% I am interested in taking the exam at all.

The difference between the two exams is clear: RHCSA is about the enteprise operating system and its features, while RHCE less about advanced enterprise operating system features and more about enterprise services (stuff like iSCSI, which is super cool and that I had only heard people speaking about).

If I pass the RHCE, I’ll write another post šŸ™‚

If you have questions, feel free to comment.

Annunci