AWS Certified DevOps Engineer - Professional Exam

Posted on Sat 29 January 2022 in Tech • 5 min read

Last week, I took and passed the AWS Certified DevOps Engineer - Professional certification exam (DOP-C01). Previously I had completed the AWS Certified Cloud Practitioner certification (CLF-C01). I got the Cloud Practitioner certification because my employer needed a certain percentage of employees to have various levels of AWS certifications in order to be in the partner program. A nice side benefit was access to the re:Invent lounges (although I was cheerfully reminded that it was the lowest level certification while I was getting my swag!). As the Cloud Practitioner certification expired, AWS told me that I had a coupon for 50% off another exam. I decided to make use of this to go for one of the top level certifications.

DevOps Engineer Exam

The exam is 75 multiple choice questions, although only 65 count towards your score (as they add new questions that don't count to see if they'd be good for future exams). You have 3 hours to complete the test, and you need 75% to pass. The questions cover 5 topic areas:

  • CI/CD
  • Security, governance, and compliance
  • Monitoring, metrics, and logging
  • High availability and autoscaling
  • Automation

Some questions were multiple choice, in that they gave you 4-5 options and had you pick the best one. Others were "multiple response", so you had 4-6 options and had to pick 2 or 3 choices from the options. I found the multiple response questions the hardest, since it was harder to narrow down the possible options and one wrong guess could affect the whole question. Each question had the option of "marking for review", so I found it nice to go back through the ones I marked just to see if a fresh look at the question might help me answer in a different way. There were a few that I did change my answer to based on some of the later questions, so it helps even if you're ready to just be done with it!

Some of the practice exams had the trivia-style questions, like having wrong port numbers or incorrect config variables. I found the real exam was a lot better at focusing on solutions and using the right tool rather than penalizing you for not knowing something easily searched, but I may have just lucked out with my set of questions.

One of the main reasons I feel like I passed is that I learned to keep an eye on what the questions was asking. It seems obvious now, but I would often pick what I would do in the situation, which may be technically correct, but the question was asking for something else. A good example is around high availability or disaster recovery. There's a lot of ways to have highly-available systems, so you have to see if the question is looking for "cheapest" or "quickest to recover" (or something else!). This is why I tried to read the wrong answers to practice tests, as it helped me internalize the options available and how much each cost in terms of money and time and effort. Sometimes, "writing a custom bash script" was the right answer, even though I wouldn't have done it personally.

Exam Preparation

I found the following study materials helpful, in rough order of my recommendation:

  • Tutorials Dojo: AWS Certified DevOps Engineer Professional Practice Exams 2022 by Jon Bonso - For $15, this is a fantastic set of resources. There are 2 sets of 75 questions, and you can either take them "exam style" where you have a time limit and don't see your scores until the end, or you can take it in "review mode" so you can see the explanation as you go through each question. I went through both sets at least twice, and it was incredibly helpful for seeing what I knew, but also reading the explanation regardless of if I was correct or not. The explanations have full links to AWS documentation too, and will explain why the other answers were wrong (even if you got it right, which does help).
  • AWS SkillBuilder: Exam Readiness: AWS Certified DevOps Engineer – Professional - This is the only set of questions I used that was grouped by topic, which helped when I was trying to focus on a certain area. There are 4-6 questions in each topic, so not a lot, and the explanation of the answer was in video form (which doesn't work as well for me). The explanations also often boiled down to "well this is the wrong answer because it can't be right", which was usually unhelpful. However, the section videos that were longer and explained the things you needed to know for each topic were great. They had little tidbits of what to expect on the test and what you needed to know. I found it extremely helpful to review each of those videos multiple times, but I skipped the question videos after I had seen them once.
  • Udemy: Practice Exam | AWS Certified DevOps Engineer Professional by Stephane Maarek and Abhishek Singh - This was on sale when I got it, so for $12 it was great to have another set of 75 questions. This test doesn't let you review the right answers between questions, but does let you review afterwards and explains the answers.
  • AWS SkillBuilder: AWS Certification Official Practice Question Sets - It's only 20 questions, but it's free! I like that this shows you the answers and explanations as you go, although the explanations aren't as detailed as the Tutorials Dojo set.
  • AWS: AWS Certified DevOps Engineer - Professional Sample Questions - It's only 10 questions, but they're different questions than any of the other sites. It's in PDF format, so it's hard to answer one, then review the answer without seeing the answers to other questions. That said, it was useful for me to write down my answers and thoughts, then review the answers at the end. Also, it's free!

Topics I Didn't Know

Although the questions occasionally mention third-party tools, almost all of the questions expect you to use AWS tools for these areas. I'm mostly familiar with Github, so I had to map my knowledge of Github to AWS tools like CodeCommit, CodePipeline, and CodeDeploy. I had some hands-on familiarity with Elastic Beanstalk, but there were a lot of questions around deployment options that I had to learn since I had only really done basic deployments. I also knew enough about CloudTrail and Cloudwatch, but often got stuck on knowing what would emit or accept a Cloudwatch Event instead of a metric alarm.

One benefit of working with AWS for so long (and doing the Cloud Practitioner certification) was that I had at least a high-level familiarity with most of the AWS services. A lot of that bled over into the DevOps Professional exam, in that you had to know when you would use Macie vs. GuardDuty vs. Inspector vs. X-Ray. I did have to review a lot of those services that I had never used first-hand, but the good news is that you don't need to know config details of a lot of them, just what they did and when you'd use them.