Tips for passing Certified Kubernetes Administrator (CKA) exam

Contrary to many reports [1][2][3][4], the exam is very adequately timed. There are many questions with lower grading that you should be able to solve in a matter of minutes. In fact, I had to double check the exam info on multiple occasions to make sure I didn’t register for a CKAD instead (Certified Kubernetes Application Developer). I advise against reading all the questions and prioritising them in any way. You should be able to do them one by one. There may be a question or two that will take a slightly longer than you will feel comfortable with. Feel free to skip those questions and return to them later. To keep yourself organized, you can’t do better than using tmux.

Named tmux windows 🔗︎

Even though I don’t really use tmux on a day-to-day basis (I heavily rely on tabs and panes in iTerm2), I’ve memorized those few commands that help me pass the certification. Immediately upon starting the exam I started a tmux session with tmux new -s cka. Naming the session is optional, but at this point I wasn’t sure what the experience would be. Even though I didn’t need it, it would allow me to detach from tmux, create different session and return to the original one back again. I created a new window for each question, conveniently indexed same as the exam questions. When completing (or skipping!) a question I renamed the window appropriately (Prefix ,). This allowed me to leave a question but return to the same work in progress at any time. Furthermore, a choose-tree (Prefix w) provided with a nice overview of all the questions.


Tmux window tree listing all windows in current session. Ignore the hostname – I've recreated the setup on my local machine.
Tmux window tree listing all windows in current session. Ignore the hostname – I've recreated the setup on my local machine.

List of all tmux windows with a preview in the lower third. Each question has a dedicated window, with the index matching the question number. Conveniently the exam has a question #0 which is an overview of all the rules.

During one or two questions I created multiple panes and connected to remote servers. This allowed me to stay organized and complete the question on the correct server.


Multiple side by side terminals in a single tmux window.
Multiple side by side terminals in a single tmux window.

A single tmux window with three panes. Top one for the main server the exam is controlled from, the middle one for a master node used in a specific theoretical question and a worker node in the lowermost pane. This feature is optional and you can do with just windows, but it’s as simple as new pane (Prefix "), change layout (Prefix Space) and close pane (Prefix x).

ABC: Always Be Copying and Pasting 🔗︎

The current CKA exam is implemented with xterm.js. I was sceptical before starting the exam because https://www.katacoda.com/ uses the same library but copy&paste in tmux does not work properly there. Even though I planned on using tmux extensively during the exam, I would sacrifice it for the ability to paste from documentation. However, the CKA exam is implemented quite well and copying&pasting the text worked reliably (between all pairs of the documentation, tmux panes and exam notepad). The exam itself may contain many identifiers such as kubernetes contexts, pod and image names, filesystem paths and kubernetes selectors. Make sure to always copy those from the assignment instead of trying to type them manually.


[1] “CKA is a tough exam” https://medium.com/platformer-blog/how-i-passed-the-cka-certified-kubernetes-administrator-exam-8943aa24d71d

[2] “The exam lasts 3 hours, i found it very challenging and well-made.” https://medium.com/@ikaboubi/my-feedback-about-cka-and-ckad-e82a35585fe9

[3] “This exam is tough, but you should be able get through with some work” https://medium.com/@arunbalasubramanyan/how-i-successfully-became-a-certifed-kubernetes-administrator-ee4290ead073

[4] “The test is difficult but passable, don’t stress too much over it.” http://ralphmcneal.com/how-i-passed-the-certified-kubernetes-administrator-cka-exam/