Recently I obtained my Certified Kubernetes Application Developer (CKAD) certification. This was the second Kubernetes exam I took from the Linux Foundation in as many months. I’ve really enjoyed studying for these certifications. I know I can’t believe I’m saying that. But the practical exam format has been a nice change from the common multiple choice we’re all use to. In my previous post on my CKA journey, Certified Kubernetes Administrator Achieved – Why, How, And All That Stuff, I discuss a lot topics I found myself, and others, asking. For this post I thought I might focus a little on the comparisons I found between the CKA and CKAD certifications.
I guess firstly I decided to take the CKAD as a way to continue my Kubernetes study. I found there to be a lot of cross over between the CKA and CKAD certifications. If you have the time and energy during your study it’s well worth trying to pursue both exams back to back, especially while the knowledge is fresh in your mind. As with the CKA, I used another Udemy course by Mumshad Mannambeth for a study guide. This course was spot on for exam content. Broken up into the exact exam syllabus categories and sections. This made studying sections very easy for required exam content. The previous CKA training course I took from Mannambeth, as great as it is, was slightly out from the CKA exam syllabus. This is no fault of the course though, at one point I’m sure it was aligned, but with the CKA exam syllabus changing and getting a revamp back in September 2020, Mannambeth’s course is now playing catch-up with required training material.
If you base your study on the Udemy courses by Mannambeth, as I did. You’ll find that the CKA course covers 90% of what’s in his CKAD course plus much much more study content required for CKA certification. To break it down as best I can and without it getting too confusing. The most notable differences in the CKAD Udemy course, which isn’t covered in the CKA Udemy course, is that it has the additional content of Jobs & CronJobs and LivenessProbes & ReadinessProbes. Two topics specifically required for the CKAD exam. What all this means is if you’ve been studying for the CKA certification there’s only small additional content to move onto a CKAD certification.
That brings me onto which exam to take, and if you’re thinking both, which order might be best? I guess the CKAD exam felt easier than the CKA. I know that’s a pretty subjective view point from myself. Having already studied for the CKA certification I had that foundation starting point for my CKAD journey. With that said, the CKAD certification focuses very largely on PODs and POD management. Whereas the CKA covered much of the same plus a strong additional focus on management of the Kubernetes stack. If you’re looking to ease into Kubernetes and looking for the easiest path to certification it would have to be CKAD. It’s definitely less overwhelming in content compared to the CKA. Depending on your study experience and how well you do in the CKAD exam you could then move onto the CKA. This approach will no doubt require a lot of additional study to skill up from CKAD to CKA.
Now if you’re not in a rush to obtain a certification and you’re looking for a good all round holistic view of Kubernetes, going for the CKA certificate first is a great path to start with. You’ll definitely come out of it with much greater knowledge than if you only did the CKAD. The benefit going down the CKA path first is if you do well and pass the CKA, moving onto and taking the CKAD should be relatively easy.
The CKAD exam will, of course, require you to learn a number of different topics. Though what your are required to learn tends to be at a higher level in comparison to the CKA. As an example. The CKA exam will expect you to know how to create and consume a Network Policy from scratch. Whereas the CKAD will more expect you to just understand how to consume a pre-existing Network Policy.
I found the style of questions between CKA and CKAD to be slightly different. In the CKA exam you would be given an objective and it was up to you to figure out what that is and how to achieve it. The CKAD exam was a little easier in that it was more clearly defined in what you needed to do. There was less ambiguity and most of the time specifically told what you needed to do.
Another interesting difference I found was how the scoring of questions worked. In both exams each question lists its weightage, or in other terms, how many points it’s worth overall in the exam. In both exams this is great for keeping track on how well you’re doing to achieve that passing score. The difference between exams came in how much weightage a question was worth. In the CKA exam, hard questions are worth more points while simpler questions are worth less. At least that was my opinion. In the CKAD that’s not necessarily the case. Easy questions could have a higher weightage while much more difficult and time consuming questions could have a much lower weightage. So much so that I felt some questions weren’t even worth attempting. Something interesting to watch out for.
Overall the journey to CKAD is quite satisfying when you achieve it. You’ll gain a good solid understanding of Kubernetes concepts and become comfortable with running and managing PODs. It’s certainly a good starting point if you’re wanting to enter the Kubernetes world. If you want to know more about the CKA certification and my exam experience you can view my Certified Kubernetes Administrator Achieved – Why, How, And All That Stuff post.