I have been working on Kubernetes for around 5–6 months at my current client site. I had no prior Kubernetes exposure and I had some experience with Docker/containers. I ramped up pretty quickly reading the following books:
- Kubernetes in Action
- Kubernetes Up & Running
- Kubernetes Patterns: Reusable Elements for Designing Cloud-Native Applications
From an hands-on perspective, I am heavily involved with Azure Kubernetes Services and related Azure services.
I opted to take the CKAD over CKA (admin) because I wanted more exposure from a developer perspective and managing manifests. I’ve been busy on building an AKS platform and using many open source projects which didn’t give me as much developer experience. Also, the CKA covers a lot of topics that are abstracted from you when using a PaaS service such as AKS (etcd, backups, master nodes, scheduler, controllers, etc). I plan on following up with CKA in the new year.
Preparing for the CKAD gives you solid exposure to deploy applications on Kubernetes. For the exam, you don’t really need Docker experience, but it’s a must in real life unless someone just tosses containers over the fence for you to create manifests. The exam is solely on Kubernetes and does not require knowledge of any external projects.
- CKAD Exercises — Sample GitHub repo with sample tasks for each of the exam objectives. This is your 1st step in determining your strengths and blind spots. Do each task against a cluster, practice, practice, practice. Another repo provides similar tasks.
- killer.sh — CKAD simulator that is basically a perfect replica of the exam environment. It has 20 labs and 3 preview labs which mimics the real exam breadth very closely. I cannot recommend this simulator enough to prepare you for the exam. It ~$45 after exchange rate. The simulator gives you 2 sessions where you are given an environment to perform the sample test. I did the simulation the night before the exam to get in the groove for the exam. Unfortunately, I took close to 3 hours to complete all the tasks when I need to finish under 2 hours. This gave me a real sense of the speed I need to reach to complete the exam. From what I hear, time is the primary reason people fail the exam. I consider myself quick at completing tasks and this was an eye opener. The simulator was a tiny bit harder than the exam.
- CKAD Challenges — Series of 13 challenges from the author of killer.sh
Both the CKA (admin) and CKAD (developer) exams are proctored using examslocal.com and can be taken from home. The exam is fully hands-on and you are allowed to use online resources from kubernetes.io/docs. The exam has 19 labs and you have 2 hours to complete (less than 7 mins per lab). CNCF exams are purposefully time restricted so that you can’t research much; you have to know your craft and get it done quickly.
The exam costs $300 USD and gives you a retake (I’d prefer one take and less cost to be honest). It looks like the exam is graded manually because you have to wait 1–2 days to get your score. A minimum of 66% is required to pass
The exam environment allows you to have multiple screens, but you will need to screen share all of them with the proctor. A large/wide monitor is highly recommended so you can have 1 browser window for the questions/terminal and one for the kubernetes.io documentation
- Be fast, really fast. Take any shortcut you need to get the task completed. kubectl run…. is your friend to generate manifests that you can edit and then dry-run and then apply.
- Bookmark relevant pages from kubernetes.io — Preparing a bunch of bookmark to knowledge entries will greatly speed things up to reach the info you need. Below is some of the bookmarks I had and I used a good 75%!
- Practice Practice Practice — If you are not a wizard at using kubectl and creating/updating manifests, do not attempt the exam. Use the CKAD simulator to give you a sense of preparedness.
- Skip questions if you have the answer in mind right away. Each question is weighted between 2 and 8%. You want to complete the higher ones and earn some points as quickly as possible. Some of the higher percentage ones were not much longer to complete than the 2% ones. Track your progress in the notepad that is available to you.
This exam was a rush and fun to do. This was the first cert I’ve done that was fully hands-on and I truly believe this is the way all exams should be. Microsoft started introducing labs into their exams, but not to this level. I finished the exam with 2 minutes to spare and it was a rush.
The beauty of performance based exam is that you can validate your work to ensure you met the requirements. So when you complete the exam, you KNOW how well you did. In the case of the CKAD, it is still a waiting game to get the final score.
It took 36 hours till I got my exam score. Smashed it at 88% :)