[GleTto][Udemy] 【Korean Subtitles】 DevOps: A Review of "Mastering Kubernetes"

This review was written after taking a course sponsored by Gltto x Udemy.

Introduction 🙋‍♀️

Since becoming a backend engineer, I’ve often been responsible for basic deployments. Through this work, I unknowingly acquired a lot of knowledge that’s common to DevOps professionals. For that reason, I’d vaguely decided that I “should study Kubernetes,” but I ended up putting it off for a long time.

When I heard that Geul-to was offering a Udemy course as part of a great opportunity, I chose this one. I’d like to share my thoughts after completing the course.

Course Review 📚

What I Liked

I gained an understanding of the big picture of Kubernetes

I learned a lot about the architecture of Kubernetes itself. I didn’t really know what components make up the Kubernetes ecosystem or how they work, but the course explained it step by step in a clear and methodical way. I also found that there are quite a few concepts similar to Docker, which made studying it even more enjoyable.

That’s why I think this course is best suited not for experienced DevOps professionals, but for those who have basic Docker knowledge but haven’t used Kubernetes much, or for people who are just starting to get interested in DevOps and want to learn more.

Hands-on exercises deepened my understanding of Kubernetes

Basically, every lecture included hands-on exercises, so I was able to follow along step by step and more easily grasp each Kubernetes command. It was helpful to organize my understanding of commands I had previously just typed without fully understanding them—figuring out what they were used for and in which situations.

Also, early in the course, the instructor provided detailed instructions on how to do the hands-on exercises on a local computer, which was quite helpful to me. I had felt a bit overwhelmed when I heard that I’d need at least three servers to set up a cluster with master and worker nodes, but the course showed me how to study using just a single local computer.
(To be honest, I need to reflect on this personally… I feel I should have looked into it properly, since it’s actually a widely known method.)

From the Absolute Basics to Advanced Topics

While the basics covered general Kubernetes concepts and related commands, the advanced section provided detailed instructions on setting up a Kubernetes environment for actual orchestration. I gained a clearer understanding of ConfigMaps and IngressControllers—which I’d used a little here and there before—and also learned many other concepts I hadn’t properly studied yet. (Helm charts are a good example of this.)

Areas for Improvement

The course felt a bit outdated

I didn’t notice this at first, but it became apparent as I looked at the examples. The course showed YAML examples with low apiVersion numbers. When I selected the course, I was aware that it had last been updated in 2021. However, since I’ve encountered cases in real-world work where the apiVersion differs, I found this slightly disappointing.
The Kubeless examples can also be considered outdated technology. I couldn’t find a Kubeless repository for the hands-on exercises… Even repositories with the same name (provided by different organizations) hadn’t been updated since 2021 and had been archived by their owners 😥 The fact that some of the examples were already no longer being maintained was the biggest disappointment.

Of course, my primary goal was to learn the basics of Kubernetes, and since the course as a whole was easy to follow for studying the fundamental concepts of Kubernetes, I decided to finish the entire course first and then pursue further study.

Personal Reflection 📝

• While taking this course, I had the opportunity to deploy a service directly to a Kubernetes-based server at my company, which became a great learning experience in many ways. Although I faced some challenges using a cloud platform that was somewhat unfamiliar to me, this course was fundamentally very helpful.
• I’d like to gain more hands-on experience with the Kubernetes services offered by various cloud platforms. Since this course was conducted on AWS and I was able to run some simple tests there, I found myself wanting to try out the servers offered by other platforms as well. Of course, I think it would be most effective to choose the platform that’s most widely used in my actual line of work.
• I took this course on my own, but I’m left with some regret that I didn’t join a study group. While it wasn’t easy to keep up with the lectures consistently, I especially regretted not having the chance to hear from someone with more hands-on experience than me. If I take another course in the future, I think it would be a good idea to try forming a small study group.

In Closing 🤗

I’d been putting off studying Kubernetes little by little, having only heard that it has a steep learning curve, but once I actually gave it a try, it wasn’t as difficult as I’d imagined. Of course, simply taking this course doesn’t mean I’ve fully grasped every concept. And theoretical study alone isn’t enough. I think the most important action item is to internalize the concepts by actively applying them in real-world work scenarios. I also need to identify what additional topics I should study so I can move on to the next level of courses or organize a study group.