Taking the CNCF Certified Kubernetes Administrator exam was an interesting opportunity to broaden my knowledge on Kubernetes. Before taking the exam and the matching course, I already came into contact with Kubernetes on a daily basis doing my job. This surely helped a lot in taking this course and exam, but more preparation is always a plus, and you never stop learning.

With this blog post, I hope to provide you with tips and better prepare you for the exam.

WHY CKA?

As you may or may not know, the CNCF has two different types of Kubernetes related exams: Certified Kubernetes Administrator (CKA) and Certified Kubernetes Application Developer (CKAD). They each have their matching CNCF course in preparation for the exams.

The CKAD curriculum targets developers and focuses more on designing, building, configuring and monitoring applications for Kubernetes. It does this using the core concepts of Kubernetes.

The CKA curriculum also touches the core Kubernetes concepts but it’s focus lies more on the engineering part of Kubernetes. It aims to educate the person taking the course to perform Kubernetes administration tasks, such as cluster installation with kubeadm. The CKA curriculum touches more topics and the exam takes longer to complete than the CKAD one.

PACE YOURSELF

I had access to the Kubernetes Fundamentals course. This is the online, self-paced CNCF course that you can follow in preparation for the exam. It has 35 hours of course material with a total of 16 chapters. This does not seem much, but can be overwhelming when learning, so be sure to actually pace yourself. Don’t schedule your exam directly after completing the course as you will need some time to let it all sink in. Maybe even recap everything you learned.

USE OTHER MATERIALS

The Kubernetes Fundamentals course is not the only thing you can do when preparing. You also have this Udemy course or this Linux Academy course. I personally did not follow any of those two, but it has a great rating and comes with some practice tests.

And of course, Google is your friend.

KUBERNETES DOCS

The Kubernetes documentation plays an essential part in every course, as it is referred to often. This doesn’t mean that you have to learn everything by heart, but you need to know how the docs are put together. When asked about a certain topic, be sure you can navigate the docs when you don’t know the answer to it, as you are allowed to open one browser tab with the official Kubernetes documentation during the exam. But if you’ve never taken a look at the documentation, this is hard.

SETUP

I used Oracle’s VirtualBox to set up some virtual machines to use during my course. This will require you to have some Linux knowledge, just as you need some during the exam. I used a CentOS distribution, but for the exam, you will use Ubuntu16 (as of today). So make sure you use the correct distribution!

KUBECTL

During the course and on the exam, you will make use of the kubectl command line tool a lot. So my advice is to really get to know it. There’s always more to learn when you think you know something, especially when it comes to a command line tool :).

It’s also very handy if you can work with tools that will help you manipulate the output of other command, tools as grep, tail, head, cut, etc. come in handy.

CURRICULUM OVERVIEW

During the course and on the exam, you will make use of the kubectl command line tool a lot. So my advice is to really get to know it. There’s always more to learn when you think you know something, especially when it comes to a command line tool :).

It’s also very handy if you can work with tools that will help you manipulate the output of other command, tools as grep, tail, head, cut, etc. come in handy.

Use the curriculum overview to check what skills are required per topic. This is probably the most important tip of all. I found this repository on GitHub where the owner took the time to link to the Kubernetes docs for each skill. I used it to lookup documentation for each skill and do some hands-on exercises where possible. For the exam, you will need these skills, so make sure you have some knowledge on each of these topics.

Not every topic is covered, or up-to-date, so try to look for the correct documentation yourself. This is already a good check to know you can navigate the documentation :).

EXAM TIPS

EXAM ENVIRONMENT

Clear your desk, this will make the process of starting your exam easier. Also make sure you are in a quiet environment. The CNCF provides an exam tips document found here (April 2020) alongside the rest of the resources.

SKIP

You will need your 3 hours of exam time, so do skip questions that you don’t directly know the answer to. The questions can be marked for later review (by yourself) so you can easily find your way back to them. This way, you can keep these questions for the end when you have an answer for all other questions. Also, for me, the question tended to go from easy to difficult.

You could also keep a score of completed questions as every question has a scoring. Some outweigh others. This way, you could focus on the questions which are supposed to be easier when you are in need of time.

DOCS

You are entitled to 1 browser tab with the official Kubernetes documentation (as of now), so use it. You can also use the search field to look for something in the documentation, but make sure you only click official documentation links.

KUBECTL

Again, I can’t really stress how important this part is. You can do a lot with this tool. Great examples are some of the things you can find in the Kubernetes cheat sheet doc, like creating a service for a resource with kubectl expose or quickly spinning up a pod with kubectl run or scaling a deployment with kubectl scale.

Use the kubectl explain command. This command can help you finding documentation about a specific resource. Extremely handy when you want to find out how you have to write the spec for that specific resource, or figure out which apiVersion that resource uses.

REUSE RESOURCES

You will probably find yourself creating a lot of resources. Instead of creating these spec files over & over again, use the kubectl command to create one quickly or fetch an existing resources’ yaml with kubectl get <resource> <resourceName> -o yaml. Write the ouput to a file and modify so it suits your needs.

PRACTICE

I used this CKA practice environment to get a feel for the exam (beware, it takes time to setup properly). It provides you with an environment where you can complete the questions that are posed in this environment. The questions give you a good feel for what you can expect. Or, you know, you can just use the questions and find the answers.

RESULT

I succeeded in completing the course and achieving my CKA certification with a scoring of 90%. I only struggled with 1 question as time was running out quickly, so keep your watch close and come prepared. Good luck!