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Certified Kubernetes Administrator (CKA) Study Guide
Certified Kubernetes Administrator (CKA) Study Guide
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August 9, 2025

Kubestronaut Journey Part 4: Kubernetes and Cloud Native Security Associate (KCSA)

by Alpha01

KCSA Badge

The Kubernetes and Cloud Native Security Associate (KCSA) exam is a an interesting one. Much like the other associate level exam, Kubernetes and Cloud Native Associate (KCNA), this is a traditional question and answer exam. A lot of the object objectives on this exam are theory based, like Cloud security models, Security compliance frameworks, and general basic level of Pod/Container security related configuration in Kubernetes.

The major motivation for me on embarking on this Kubestronaut journey has been to learn new things Kubernetes that I otherwise wouldn’t know about. Certainly on all exams thus far have been the case. On this exam in particular I just learned about Pod Security Standards (PSS) and Pod Security Admission (PSA), which were new to me even after working with Kubernetes on an almost daily bases the last five years! (I use Kubernetes Admission Controllers instead)

I’m almost at the finish line on achieving Kubestronaut, now the final exam I need to pass is arguably the most difficult one. Certified Kubernetes Security Specialist (CKS)

Difficult Level

This was an easy exam. However unlike the scenario exam exercises or other question and answer exams where I have somewhat of an idea of what the answer will be. I felt as if on the questions that I answered wrong, were completely guesses on my part. Although the exam is easy in my point of view, I can certainly see it a being tricky to others. There were a few questions that touch topics I have zero to no working knowledge about, like AppArmor and seccomp.

Study Resources

Tags: [ kubernetes kubestronaut ]
July 24, 2025

Kubestronaut Journey Part 3: Certified Kubernetes Administrator (CKA)

by Alpha01

CKA Badge

Quite a lot things happened between the six months of my CKAD renewal and now the CKA that allowed me to finally take the exam.

Needless to say I was able to successfully renew my Certified Kubernetes Administrator (CKA) certification for two more years and now I’m just two steps away from becoming a Kubestronaut. The next exam that I’ll be doing will be the Kubernetes and Cloud Native Security Associate (KCSA).

Difficult Level

The only major difference between the version that I took over three ago from the one I just passed was that the current version had less question regarding etcd administration and Kubernetes upgrades (kubeadm approach). Aside from these two points, the questions were mostly very similar. Thus said, I did had to study new features like the Kubernetes Gateway API.

I don’t think anyone that took and passed the exam three years, would have a problem passing this exam now.

Study Resources

Tags: [ kubernetes kubestronaut ]
January 5, 2025

Kubestronaut Journey Part 2: Certified Kubernetes Application Developer (CKAD)

by Alpha01

CKAD Badge

In my continuation of becoming a Kubestronaut, I took the Certified Kubernetes Application Developer (CKAD) exam. Unlike the Kubernetes and Cloud Native Associate (KCNA) which is a question and answer exam, this exam is a hands on lab performance test (which personally I prefer). However this time around, their was one massive self-inflected gotcha that made this exam more difficult that it should’ve been. I opted to use my 13-inch 2021 M1 MacBook Pro for the exam. This made it extremely difficult to use the exam application due to the limited space of the remote workstation we have work in to do the respective exam assignments. Right from the very start I became very agitated on the screen real estate that I had access too. I wasn’t able to easily switch between the Kubernetes documentation and the remote shell sessions. So I ended just using the built-in kubectl explain command line documentation for guidance. This worked well, except that I took way longer looking up information up to the point where I almost ran out of time and had to rush through the last 5 questions fearing that I wasn’t able going to finish the exam in time and fail due to not being able to answer the question! That’s about 1/3 of the entire exam!

Difficult Level

The questions ranged from really easy, to more mid-level and advanced (albeit simple) questions. The questions were straight forward. I practically used the same study material that I used when I first originally took the test on January 2022. Which was the Udemy Kubernetes Certified Application Developer (CKAD) with Tests course as well as the newly release O’Reilly Certified Kubernetes Application Developer (CKAD) Prep Course and it’s companion book Certified Kubernetes Application Developer (CKAD) Study Guide, 2nd Edition for good measure.

Although I’m disappointed at myself on the final score, I was able to pass the exam with a score of 71/100. Not the score that I wanted, but given that I didn’t relied on using Kubernetes Documentation, I’m content. Next on my list will be completing (recertifying) the Certified Kubernetes Administrator.

Needless to say, for my next exam I’ll be connection my laptop to an external 27 display!

Study Resources

Tags: [ kubernetes kubestronaut ]
December 28, 2024

Kubestronaut Journey Part 1: Kubernetes and Cloud Native Associate (KCNA)

by Alpha01

KCNA Badge

It’s been almost three years since I’ve obtained the Certified Kubernetes Application Developer (CKAD) and Certified Kubernetes Administrator (CKA) certifications. I was originally planning on recertifying these two Kubernetes certifications, however while at KubeCon last month, I was excited to learn about the Kubestronaut Program, which is a recognition to Kubernetes professionals that pass all five Kubernetes certifications. So I decided to accept the challenge and not only recertify my existing two certifications, but also take and pass the remaining three other certifications Kubernetes and Cloud Native Associate (KCNA), Cloud Native Security Associate (KCSA), and Certified Kubernetes Security Specialist (CKS) so I can become a “Kubestronaut”.

For my first exam on this journey, I’ve decided to start with the Kubernetes and Cloud Native Associate, which is the easiest of them all. To prepare for the exam, I used the Udemy Kubernetes Certified (KCNA) + Hands On Labs + Practice Exams course (8 hours) and the O’Reilly Kubernetes and Cloud Native Associate (KCNA) course (5 hours).

Difficult Level

Low, this was a very easy exam. I think anyone with moderate Kubernetes knowledge, can just use the Udemy Kubernetes Certified (KCNA) + Hands On Labs + Practice Exams course as their only study material can pass this exam. Thus said, this is also assuming that the candidate has also basic high-level knowledge of cloud and cloud native technologies. I’m pretty confident that I could’ve taken this exam without going through any of the mention study courses and I still would’ve easily passed it. However since this is meant to prepare myself for the more challenging exams, I’m still glad I study for this exam. I even learned new stuff along the way which is the main point of this entire journey!

I was able to successfully pass this exam with a score of 95/100. Next on my list will be completing (recertifying) the Certified Kubernetes Application Developer.

Study Resources

Tags: [ kubernetes kubestronaut ]
December 14, 2024

Simple Bash KVM Virtual Machine Startup and Shutdown Script

by Alpha01

Given that I don’t want my Intel NUC homelab mini pc to sound like a jet engine all day. I wrote a simple bash script that would automatically startup and shutdown my kubernetes VMs easily each day. The script is cron friendly and it works like a charm.

# Start VMs
./rancher.sh start

# Stop (non-gracefully, use virsh shutdown instead)
./rancher.sh destroy 
#!/bin/bash
# set -x

VMS="rancher rke2"

action=$1
if [ -z $action ]; then
    echo "No action passed"
    exit 1
elif [[ "$action" != "destroy" && "$action" != "start" ]]; then
    echo "Unsupported action: $action"
    exit 1
else
    echo "Doing $action"
fi

function vm () {
    vm=$1
    current_vm_state=""
    tmp=$(virsh list --all | grep " $vm " | awk '{ print $3}')
    if ([ "x$tmp" == "x" ] || [ "x$tmp" != "xrunning" ])
    then
        echo "$vm does not exist or is shutdown!"
        current_vm_state="destroy"
    else
       echo "$vm is running!"
        current_vm_state="start"
    fi
    if [ "$action" != "$current_vm_state" ]; then
        virsh $action $vm
    fi
}

for vm in $VMS; do
    vm "$vm"
done
Tags: [ bash rancher kubernetes ]