What's on the Certified Kubernetes Application Developer (CKAD) Exam?

The Certified Kubernetes Application Developer (CKAD) is an intermediate-level exam offered by the Cloud Native Computing Foundation (CNCF). It’s aimed at systems administrators, developers, and engineers who want to validate skills in designing, building, and configuring applications for Kubernetes. 

The CKAD exam costs $375 and is composed of about 19 questions. In order to pass, the candidate needs to score at least 66 out of 100 points. You get two shots at the exam in case you fail the first time.

Test takers are allowed two hours for the exam, which is purely command line based —  meaning there are no multiple choices questions to be found! With that being said, it’s very important to understand what is on the exam, which is exactly what we’re about to cover. As someone who has taken and passed the exam, I will offer some suggestions that assisted me in clearing the test.

Prepare for the CKAD Exam With the Right Training

If you’re planning to take the CKAD exam or might be in the future, you should check our CKAD online training course. Trainer Trevor Sullivan created the course with the CKAD certification in mind, so it should be an excellent study resource.

If you are new to Kubernetes or don’t have much experience with it, we offer a variety of Kubernetes training that can get you up to speed, no matter your comfort level with Kubernetes. Start a free week with CBT Nuggets and start training today!

What Questions are on the CKAD?

In order to pass the CKAD, you need to prove your competency in the following domains:

The following descriptions are by no means all-inclusive. It’s just to give you a general idea of what to expect in each section.

Application Design and Build

For this domain, expect questions about creating k8s resources. For example, this could be topics such as creating an ingress resource to connect to a service. Often, you will be given an existing resource and asked to modify it. Also, think about how Pods are designed. It is important to know how to execute commands upon Pod startup, and how to request CPU and memory resources.

Application Deployment

This section refers to a deployment configuration. It is important to understand how to build and scale deployments, as well as how to roll back to different deployment revisions. This portion also covers helm installation and configuration. Don’t worry too much about helm, they just want you to have a basic understanding of how it works.

Application Observability and Maintenance

This is all about creating Readiness Probes, Liveness Probes, and exporting logs. It’s critical to have a thorough understanding of how to execute commands, or probe endpoints using both probe types. Make sure you know how to move logs to different locations in a Linux environment.

Services and Networking

Make sure you know how to expose a service imperatively. Learn how pods and services are related to each other. Understand the four different types of services especially ClusterIP and NodePort. Network policies and resource types are included here as well. These determine what sort of traffic can or cannot flow to certain resources. 

Application Environment Configuration and Security

ConfigMaps and Secrets make up the meat and potatoes of this section. Know how to export ConfigMap keys and values from a file into the resource itself. Generic secrets will inevitably show up on the test, verify you know how to use these and how to encrypt and decrypt them using base64 encoding.

CKAD Tips for Potential Exam Takers

As previously mentioned, I passed the CKAD certification exam. So, I wanted to share some advice that may help you prepare for testing day and set you up better for success on the exam. 

1. The CKAD exam is composed of one command line terminal with the question presented on the left side. Read the questions very carefully. Often, you are asked to perform actions in different namespaces. That means you could do everything right, but if it is in the wrong namespace, your goose is cooked.

2. There are two ways to create Kubernetes resources: imperatively and declaratively. Declaratively means creating a YAML file to define the resources. This can be thought of as IaC, Infrastructure as Code. However, during the exam, you don’t have time for that, so you need to define resources imperatively.

That means it is important to utilize the command line to create pods, expose services, scale deployments, and more. During the exam, I created a couple of shortcuts to do this quickly by using linux aliases and exports. Here are the ones I used.

export dry=“—dry-run=client -oyaml”

Alias kd=k describe

Personally, these are the only two I used. However, using this principle can save precious typing time during the exam.

3. Learn how to use the text editor VIM. It’s critical to have a basic understanding of how to save, edit, and manipulate text. VIM and nano are the only text editors accessible during the exam, choose one of them and get good with it. If you choose VIM as I did, then make sure to add the following commands to the .vimrc file right when the exam begins. It will save a lot of hassle when copying and pasting code from the Kubernetes documentation.

:set shiftwidth=2

set tabstop=2

set paste

set expand tab.

4. Nineteen questions within two hours means you only have about 6 and a half minutes to do each question. In my experience, about 30% of the questions were intricate and nuanced, and the other 70% were fairly easy. That means if you come across a question you cannot answer, skip it. It is critical to get to the end of the exam and make sure you answered all the questions you can. The exam comes with a notepad, so mark off questions giving you trouble and move on.

Final Thoughts

To be frank, the CKAD is no walk in the park. All in all, I studied for about three months. But if you continue to get your hands dirty in the kubectl CLI, you will pass the exam. The key is practice, practice, practice!