My CKS Experience

Hello everyone! In this blog post, I wanted to share my experience taking the Certified Kubernetes Security Specialist (CKS) exam.

📝 The Exam Difficulty

I have previously taken the CKA and CKAD exams, and I personally found the CKS to be more difficult than either of those. Granted, this was most likely due to my lack of exposure to the topics covered on the CKS exam in my career thus far, as a Junior DevOps engineer, but still.

In terms of a difficulty ranking, I would place the various topics on a tier list as follows:

Very Easy

These tasks usually just require one or two basic commands which can be easily found using the --help flag even if you forget them

• using kubesec to scan and fix manifest files
• using trivy to scan images

Easy

These are not particularly difficult, but they do require some knowledge and understanding of how Kubernetes works. I think that, especially if you took the CKA and/or CKAD before the CKS, these should be second nature at this point:

• setting up AppArmor profiles
• configuring seccomp
• creating network policies
• managing service accounts with the appropriate roles and rolebindings

Moderate

These tasks are not necessarily difficult, but they can be time-consuming and require a fair understanding of how Kubernetes works:

• setting up admission controllers
• editing the static pod definition files to secure the cluster

I placed these tasks in this category since validating your work can be quite time-consuming since you are editing the static pod manifests on the master node and it can take a bit for the pods to be recreated.

Difficult

In my opinion, this was the most difficult and time-consuming part of the exam. I had not used Falco before and I felt that the amount of practice I was able to get before the exam was insufficient to properly “master” it.

• managing Falco configuration
• configuring Falco rules

📚 Useful Resources

To prepare for the CKS exam, I used the course offered by KodeKloud, as well as their CKS challenges. While I found these resources to help prepare for the actual exam, I did not feel as ready and confident as I did for the CKA and CKAD. In my opinion, the course quality was not up to par compared to the other two mentioned.

That being said, I would still recommend these resources to others preparing for the CKS exam as they do in fact cover the entire curriculum, just not as well and thoroughly as I came to expect from them.

Another thing worth mentioning is that I challenged myself to get all 3 Kubernetes certifications within 3 weeks. This means that I was left with 1 week only to study and prepare for each exam. For the CKA and CKAD, this was not a problem, as the curriculum had a lot of overlap and they are also closely related to what I do at work. For the CKS, on the other hand, I do believe that a longer preparation phase would have been extremely beneficial, as I really did not feel that confident going in. While I did manage to pass, my score was considerably lower than my CKA and CKAD, which again suggests that I really should have taken more than 1 week to prepare.

💻 Technical Aspects

On the technical side, everything went smoothly this time. Unlike my terrible CKAD experience, I did not have any issues with the PSI system and the check-in process was relatively quick and efficient. The connection was stable throughout the exam with no dropouts, so I had no complaints in this regard.

I would go as far as to say it was almost a flawless experience, but since it is the first and only time things went so well, I am reluctant to make any bold claims. If I were to take another exam with PSI tomorrow, I wouldn’t expect it to go this well again, so take that with a grain of salt.

💭 Final Thoughts

Overall, while I found the CKS exam to be more difficult than the CKA and CKAD exams, I am glad I took it and I got this. It was a challenging experience, but it helped me to deepen my understanding and strengthen my skills in the area of security, both related to Kubernetes and in general. If you are thinking about taking the CKS exam, I would recommend it, but be prepared to put in some extra study time to ensure you are fully prepared.

I hope this provided some insight to anyone interested in taking the CKS exam!