My preparation for the CKA exam
The goal of this article is to be a guidance for you, so you can feel more comfortable and confident to clear the exam, do not feel afraid to comment if you have any doubts, I am always glad to help with that.
I received my badge on August 3rd with a 96% score.
About the exam
If you don’t know, this exam is maintained by the CNCF so as LFCS, LFCE and other performance-based exams, yes, you have read it right, this is a performance-based exam, so no multiple choice questions.
There will be an average of 20-25 tasks to accomplish either troubleshooting or executing normal daily tasks, and you have 3 hours to get all done.
A proctor will be monitoring you in real time and there are a lot of requirements you have to fulfill, so please, make sure you have read all the instructions below:
1. Linux Academy
Initially I have used the Linux Academy training by Chad Crowell to prepare for it, take a look on the link below:
In the moment I am writing this post, the Linux Academy platform is being migrated to A Cloud Guru, so I am not sure if the link above will work.
This training has a lot of practical labs and cover the most part of the exam, but I would not recommend you to use only this one. Actually, never use only one study path.
From my experience, this training was the best one, the practice tests are really challenging, you can really understand the concepts and get prepared for the exam. I truly recommend it!
3. Official documentation
During the exam, you can have one extra tab with the official documentation, so it is really important to understand where the information is, how to search, the keywords, everything that can speed-up your research for something.
Try to solve problems only using the official doc rather than searching on Google.
4. Kubernetes: Up and Running: Dive Into the Future of Infrastructure
This is a great book by Kelsey Hightower, and I really recommend you to go through it.
The official documentation is enough, but sometimes it’s too much technical and you cannot understand the concepts, so reading a book can help you to clarify that.
1. Local cluster with Vagrant
Sometimes you just don’t want to use the Cloud playgrounds to work with Kubernetes like Linux Academy or Mumshad’s course, so let me recommend you this great project by Janssen Lima.
Is it really straight forward, you have have to clone and run a
vagrant up and it should bring up a cluster with one master and two nodes.
You can access the master using
vagrant ssh master where you can manage everything. Easy!
If you don’t have a LinkedIn profile yet, you are losing so much… Please, create one and start making network with other engineers who took the CKA exam. Start chating with them. Ask for an advice. Perhaps he/she will have a very good tip that you can use for the exam.
3. Do not write YAMLs
DO NOT WRITE YAMLS!!! Use imperative commands to generate a sample YAML file and only edit what you would like to change. For example:
$ kubectl create deployment test-nginx --image nginx -o yaml --dry-run > test-nginx.yaml
This command will create a YAML file for deployment called test-nginx.yaml, so you can change the number of replicas, the name and everything else. Easy²!
If you need to create something that you cannot create an YAML on the CLI, like a PVC for example, get a template on the official documentation, use your time wisely.
4. Enable bash completion
You will not remember every command, so you can enable the bash completion (if not already enabled) with this command:
$ source <(kubectl completion bash)
5. Have a good webcam
Before starting the exam, you have to show your identification, like a passport for example. Therefore, your webcam has to autofocus on the document when show to the proctor, otherwise he won’t be able to see anything and you will be in trouble.
6. Do it in the morning
I did the test after my working hours. I finished the exam by 11PM, starving and really tired.
My recommendation is, if you can obviously, do your test by the morning with all your energy. I won’t say this is a hard exam, because if you study hard you and can get it done, but it is really tough. You have a lot of work to do, and you will be 3 hours without water and bathroom.
7. Double-check the topics
Double-check all the objectives here and make sure you went through all of them.
8. Learn how to troubleshoot
The toughest questions are the troubleshooting ones, and of course you must have a good understanding of it. How each component interacts with the other ones, where to get the information…
9. Understand the test
This is a general tip for every certification, but do a deep research about the test, how many questions, how it is divided, how much time do you have, read about other people experiences with it… The goal is, be aware of what you will be dealing with.
I took the most important documentation links, like the PVC one and put on my bookmarks so I could find it faster than searching on the official doc.
1. Do I really need to go through the Kubernetes The Hard Way?
If you don’t what is KTHD, click here.
This is a great step-by-step and hands-on tutorial to create a highly available Kubernetes cluster.
In my opinion, the KTHD is really important to understand about how a production cluster works in the Cloud, but it can be an overstudy for the exam.
I did the KTHD only once, copying and pasting, just to have a feeling of how it is.
If you have time, do it.
2. Do I have to have real a production experience before taking the exam?
This is something everyone says: “yes, you should have at least 6 months of experience working with Kubernetes” and this is not true.
I did this test with zero experience with production Kubernetes cluster, everything I learned on the courses, books and official documentation.
Of course, you must practice a lot, and if you study hard, you can clear the exam with no working experience with it.
Trust in yourself.
Do not overthink.
Go for it.
Perhaps you can get inspired by this picture!
If this post has helped you somehow, drop a comment right here! :)