Tower of Kubes

The Ultimate Guide to Kubernetes Books: From Beginner to Certified Expert

2024-06-26T00:00:00Z

While studying for the Certified Kubernetes Administrator certification last year, I wanted to take a deep dive into Kubernetes topics, both those covered by the certification and beyond.

As a develeap employee, I had access to all of develeap’s courses which I used to learn more about Kubernetes. Alongside that, I wanted to supplement my learning with books and practice labs. After I earned the CKA certification, I decided to review the field of Kubernetes books, labs, and courses. In part one of this article series I reviewed several of the CKA courses I took in Review of CKA Courses. In part two, I reviewed Kubernetes practice labs and mock exams in Review of Kubernetes Practice Labs. In this part (part three), I will review several of the books and written materials that I have read while learning about Kubernetes.

The Book of Kubernetes

Author: Alan Hohn

Publisher: No Starch Press

Publication Date: August 2022

Link: No Starch Press | Amazon | Penguin Random House | O’Reilly

The Book of Kubernetes (not to be confused with The Kubernetes Book by Nigel Poulton, which I have not read) is written by Alan Hohn and published by No Starch Press. I was already a fan of No Starch Press, having read many of their previous books, and this book was brand new when I first read it, so it was naturally my first choice when wanting to read more about Kubernetes.

This book serves as an introduction to Kubernetes. Although it assumes some sysadmin knowledge (and gets quite technical fairly fast), you don’t need to know anything about containers, as everything is explained—especially in the first part.

The book is split into 20 chapters across three parts. The first part, “Making and Using Containers,” serves as a fairly comprehensive overview of what containers actually are, as well as their benefits. In fact, I would go as far as to say this book might be the best explanation I’ve read about containers; too often I see simplified explanations about containers boiled down to “containers are like virtual machines but not really”. This book actually goes through the effort of explaining the technical underpinnings of containers, and how they use the fundamental capabilities of the Linux kernel, like namespaces and cgroups, to provide containers process isolation, resource limiting and network namespaces. This is first explained using Docker, the most used container tool, but later on the chapter shows how to achieve the same results using containerd as well as CRI-O and crictl. Showing how the same container image can be run through different container runtimes and tools, helped me understand the universal nature of OCI containers and the way Kubernetes can interface with containers through the CRI protocol.

The next two parts, “Containers in Kubernetes” and “Performant Kubernetes,” focus on many important Kubernetes topics. Along the book are examples which you can deploy yourself from the book’s GitHub repo. These are automated exercises that can be deployed using Ansible and run on either Vagrant (virtual machines) or AWS. These examples are very useful for hands-on understanding of the topics, and having them all automated while offering different ways to deploy – makes them very useful.

I will note that this book isn’t specifically designed to prepare readers for the Certified Kubernetes Administrator (CKA) exam. While it covers many relevant topics, there are some key CKA subjects not included, and conversely, some topics explored here might not directly align with the CKA curriculum (for example, Custom Resource Definitions). This, however, isn’t a drawback – the book excels in its own right, just keep this in mind if your primary goal is CKA certification.

Certified Kubernetes Administrator (CKA) Study Guide

Author: Benjamin Muschko

Publisher: O’Reilly Media, Inc.

Publication Date: June 2022

Link: O’Reilly | Amazon | eBooks.com

My one “complaint” about the No Starch book was that it was not a CKA study guide (it was not really a complaint, just an observation). Well, this book is! After No Starch Press, my other favorite publisher for technical books is O’Reilly, which has maintained a high standard for decades.

This book has everything you’d expect from a study guide. There are detailed explanations of everything you need to know in the CKA curriculum. There are useful tips for the exam and practice questions which are at a good level. For some of the practice questions you get automated Vagrant environments from the book’s GitHub repo, however for many questions you will have to set up a practice cluster yourself (or use Killercoda).

In some places the book mentions optionally using Kubernetes environments in Katacoda. This was a service offered by O’Reilly, unfortunately public use of Katacoda was recently shut down. This decision must have happened around the same time this book was published, but due to the unfortunate timing, Katacoda is still mentioned in this book. Fortunately this book does not really rely on using Katacoda to understand its material, it is merely offered as another option for practice. Now, Killercoda is available as a form of replacement for Katacoda (reviewed below).

Overall this book serves its purpose well as a written CKA study guide.

Learning CoreDNS

Author: John Belamaric, Cricket Liu

Publisher: O’Reilly Media, Inc.

Publication Date: September 2019

Link: O’Reilly | Amazon | eBooks.com

This book is, of course, about CoreDNS, the modern DNS server used for Kubernetes. Despite being about CoreDNS, it also focuses on Kubernetes networking and service discovery. It’s a good read for anyone who wants to understand Kubernetes networking on a deeper level. It’s more detailed than what is required to know for the CKA exam, but more knowledge is always good.

The book starts by explaining what CoreDNS is and why a new DNS for the container and micro-service was needed. It compares CoreDNS with BIND 9 (a more traditional DNS server), and explains the pros and cons of each. Spoiler: CoreDNS is not necessarily a replacement for BIND 9, they have different usages.

The book then dives deeper into how CoreDNS works with Kubernetes and etcd for service discovery, and delves into modern workflows and best practices (including Prometheus monitoring).

If you want to understand CoreDNS well, then there is probably no better book. For learning Kubernetes networking specifically for the CKA exam, this book is not the best option as it focuses on concepts that are not that important for the exam itself, while at the same time not delving too deeply into concepts which are important (such as Kubernetes Ingresses).

Kubernetes Documentation

Link: https://kubernetes.io/docs/

Of course, this is not a book but a website, one that everyone working with Kubernetes must be familiar with—and especially anyone taking one of the certification exams where this resource is allowed.

The Kubernetes Documentation has tons of relevant information; almost everything you would need to know for the CKA and CKAD exams is included in these docs. Of course, the documentation goes beyond what you need to know for the exams. If you want to become an expert on everything you can do with “stock” Kubernetes, you could read the entire documentation. Or you can focus on reading the sections that are most relevant to you.

Since I used other resources to study for the CKA certification, I did not read the documentation cover-to-cover.¹ I did, however, use the documentation frequently to reiterate the concepts that I learned, as well as during practice labs and mock exams. Whenever I needed to find out how to do something in Kubernetes, rather than searching Google, I searched through the Kubernetes Documentation first. For example, say I wanted to find a YAML template for deploying a PersistentVolumeClaim; I would go into the Kubernetes Docs and type “PVC” into the search bar, then click “ Configure a Pod to Use a PersistentVolume for Storage”, which explains PVCs and other relevant concepts.

I found this learning method to be very effective. When preparing for the CKA/CKAD exams, you should be adept at finding relevant information from the documents quickly and efficiently.² This is why I recommend using the documents as much as possible while studying. You don’t have to read everything in the documents, but you should be familiar with the content they include and how to find it using the built-in search. Configure a Pod to Use a PersistentVolume for Storage, I highly recommend exploring the Kubernetes Docs yourself and seeing what they offer. There are sections explaining common tasks, a One-page API Reference for Kubernetes v1.30, and even Tutorials.

Featured image by 🇸🇮 Janko Ferlič on Unsplash.

In fact the Kubernetes Docs can’t be read cover-to-cover because they are not a book and therefore lack a cover. ↩︎
The CKA exam has its own way of scoring things and is not public. You get a score sometime after completing the exam, but you won’t know which questions you answered correctly. ↩︎

Review of Kubernetes Practice Labs

2024-06-26T00:00:00Z

While studying for the Certified Kubernetes Administrator certification last year, I wanted to take a deep dive into Kubernetes topics, both those covered by the certification and beyond.

As a develeap employee, I had access to all of develeap’s courses which I used to learn more about Kubernetes. Alongside that, I wanted to supplement my learning with books and practice labs. After I earned the CKA certification, I decided to review the field of Kubernetes books and practice labs. In part one of this article series I reviewed several of the CKA courses I took in Review of CKA Courses. In this part (part two), I reviewed Kubernetes practice labs and mock exams. In part three, I share my take on written materials in The Ultimate Guide to Kubernetes Books: From Beginner to Certified Expert.

Killercoda

Link: Killercoda CKA Area

CKAD Equivalent: Killercoda CKAD Area

Killercoda offers free labs! Although Killercoda does offer subscriptions, the paid features which are currently included are not major. I’d say the main reason to consider a subscription is if you are using Killercoda frequently and want to support what they are doing. Honestly, what they are doing is excellent and worth supporting.

With a free account you can access various different environments and scenarios. The ones offered are very good and worth doing. I especially like the CKA Playground environment, designed to be similar to the current environment used by the CKA exam. You can use the Killecoda playgrounds to freely play around with Kubernetes, without being constrained to a specific scenario. This is really useful, for example if you just want to try out some commands to see what they do.

In addition, the environments load fast. This is impressive considering this is all available on the free tier.

Killer Shell

Link: Killer Shell CKA Simulator

CKAD Equivalent: Killer Shell CKAD Simulator

Killer Shell is created and maintained by the same team as Killercoda (led by Kim Wüstkamp), however they have notable differences. You can read their own comparison here; to summarize, while Killercoda allows you to practice exam topics, it is not an exam simulator.

Killer Shell is an exam simulator. In fact, it is the official exam simulator for the CKA, CKAD and CKS certifications (and soon the LFCT certification as well). Although using Killer Shell on its own is not free, you get two sessions included when signing up for any of these certifications.

Each session lasts 36 hours and includes an exam simulation that is designed to closely mirror the real exam environment. This means you get not only a terminal, but also a full XFCE desktop to work in. You get to work on 25 questions (plus a few extra questions) across several different Kubernetes clusters. You have a two-hour timer. However, after the two hours pass, you can continue to answer the questions at your own pace (up to the 36-hour time limit of the session).

To be honest, it’s very hard to answer all 25 questions within the two-hour limit… The questions in the Killer Shell exam are designed to be slightly harder than in the real exam. In addition, in the real exam, you are likely to get less than 25 questions to answer within the two-hour limit. My advice is not to focus too heavily on the time limit. However, do make sure you can answer all questions, even if it takes you longer than two hours. Nevertheless, you should be trying to find ways in which you can work fast and most efficiently; for example setting aliases and environment variables, and learning Vim shortcuts. These tricks will help you in the real exam, and the exam simulation is the best place to practice.

After the two-hour timer passes (which you can also end early), you get to see an automated scoring system that checks which questions you answered correctly. The exam, however, still continues in the background, and you can go back to questions and fix your answers. I noticed the automated scoring system sometimes takes a few minutes to update, which led to some confusing situations where I tried to fix an answer but had to wait a few minutes to confirm I answered correctly. Another nitpick is the automated scoring system is a bit overly strict in the way it likes its answers. For example, in one of the early questions, you have to write a shell script to do a simple task; this can be done in several ways, but in practice, the script has to be written in the exact way that the automated scoring system expects (you can’t even use a shebang, as a friend of mine found out while trying out Killer Shell). I don’t know if the real exam is as strict with its scoring as Killer Shell.

In the real CKA exam you don’t get to see which questions you answered correctly, that’s why you should practice checking your own answers. After answering questions, you should verify that you did things correctly using different commands. Again this is something which of course can be practiced within the Killer Shell environment.

As I mentioned, you get two Killer Shell sessions after signing up for a certification. It’s worth noting that both sessions will have the same questions. In my case I found that one session was sufficient for preparing for the real exam. However if you didn’t do well in the first session, then that’s a good sign you should go back to practice and learn the concepts that you struggled with. Once you are able to get a good score at Killer Shell, you will know you are ready for the exam.

As for when to take the Killer Shell exam, it is often recommended to take it relatively close to the real exam (say within one week), after you have thoroughly learned using other resources. If you are already experienced in using Kubernetes and wondering if you need to spend time on courses, you could test yourself by doing a Killer Shell simulation session first and see how well you do.

Review of CKA Courses

2024-06-26T00:00:00Z

While studying for the Certified Kubernetes Administrator certification last year, I wanted to take a deep dive into Kubernetes topics, both those covered by the certification and beyond.

As a develeap employee, I had access to all of develeap’s courses which I used to learn more about Kubernetes. Alongside that, I wanted to supplement my learning with books and practice labs. After I earned the CKA certification, I decided to review the field of Kubernetes books and practice labs. In part one of this article series (this article), I review several of the CKA courses I took. In part two, I review Kubernetes practice labs and mock exams in Review of Kubernetes Practice Labs. In part three, I share my take on written materials in The Ultimate Guide to Kubernetes Books: From Beginner to Certified Expert.

KodeKloud

KodeKloud courses are available on their own site and some are also on Udemy. Some courses and labs are only available through a KodeKloud subscription.

Certified Kubernetes Administrator (CKA) with Practice Tests

Link: KodeKloud | Udemy

The gold standard in Kubernetes courses. This course by KodeKloud Training and Mumshad Mannambeth covers everything one needs to know for the CKA exam. The explanations are clear, there are high quality slides and animations for every topic and the topics themselves are well organized. Every section has accompanying practice labs on KodeKloud (the labs are included even if you sign up through Udemy). Each lab runs for one hour but you can repeat every lab as many times as you’d like.

The course includes 22 hours of videos and in addition to the videos you can expect to spend at least that long on the practice labs. I highly recommend doing all the labs even if you don’t watch all of the videos. After every lab there is a solution video where Mumshad shows how to solve all the practice questions; these solution videos are marked as optional, you may choose to skip them when you have solved all the questions yourself; however I found that these solution videos often feature additional tips and tricks or ways to solve the problems that are possibly faster than what I did. Learning through a combination of watching videos and reinforcing the concepts through practice labs leads to very good understanding of the topics in my experience.

Some people wonder if this course alone includes all the content that you need to know for the CKA exam. In my opinion, it certainly does; this course is very thorough and combined with the practice labs it prepares you very well. In a few sections, such as Networking, the course even goes more in-depth than is needed for the CKA exam (as knowing core networking concepts is always useful). Having said that I don’t recommend skipping any sections that are not marked as optional (”Kubernetes The Hard Way” is an optional part of this course which I will cover below).

In addition, the course and labs are constantly updated to keep up with changes to Kubernetes and the CKA exam. For the rest of this paragraph I will go on a slight technical tangent; The one part I felt was missing from this course were additional explanations of container runtimes and the removal of dockershim. Kubernetes v1.24 removed dockershim support. This change is therefore relevant to the CKA exam starting from 2023 when the exam environment moved to Kubernetes v1.26. There is some confusion regarding all this and I think a video explaining this change would’ve been helpful (hopefully it gets added in the future). As of now, the course videos don’t reflect this change, however the practice labs actually do. In some of the practice labs the solution videos show Mumshad using the docker CLI, however the actual practice labs have been updated to use the crictl tool instead. Hopefully the course videos get fully updated to reflect these changes.

Overall I highly recommend this course. If you follow only one course from this list, make sure it is this one. In addition, this course also includes mock exams which I review below (in the “Labs” section).

Kubernetes for the Absolute Beginners - Hands-on

Link: KodeKloud | Udemy | O’Reilly

This course by KodeKloud Training and Mumshad Mannambeth is similar to their CKA course, however the difference is it’s designed for “Absolute Beginners” (whereas their CKA course already expects a little bit of familiarity with Kubernetes). If you have no previous experience with Kubernetes, or haven’t worked with it in a while and need a refresher, I recommend taking this Beginners course first before moving on to KodeKloud’s CKA or CKAD courses. However, despite the “Absolute Beginners” title of this course, I would still recommend having some knowledge of Docker/Podman and the Linux command line before moving on to this course (I cover some resources for learning those topics below).

The course includes 6 hours of videos and in addition to the videos you can expect to spend at least that long on the practice labs. I will note that many of the topics in this course are also covered in the KodeKloud CKA/CKAD courses, mainly everything related to the core Kubernetes concepts like Pods, ReplicaSets, Deployments and Services. There are however some additional coding exercises though for each of these topics. If you choose to do this course first you can later skip these topics when moving on to the later courses. Despite the repetition, I do think this course offers enough additional content to be worth it in its own right (although in terms of value, it is significantly shorter than the KodeKloud CKA/CKAD courses). I think its introduction to Kubernetes is very good, and in the later parts of the course you get to deploy a relatively complex Microservice Architecture across the three major cloud providers and their respective managed Kubernetes services - GCP (GKE), AWS (EKS) and Azure (AKS).

Courses - Honorable Mentions

TechWorld with Nana

Link: Website | YouTube Channel

Anyone learning DevOps has probably come across Nana’s insightful videos on YouTube.

Nana has many videos on her YouTube channel about Kubernetes which are offered for free! Then on her website she offers full courses. The price difference is stark though, especially compared to the wealth of free content she has on her YouTube channel. Her courses are quite pricey compared to other options. I can’t make a judgement about their value though since I have not tried her paid courses. So instead I will focus on the value offered by Nana’s free YouTube videos.

The TechWorld with Nana YouTube channel has videos on many topics. Kubernetes is certainly one of the prominent topics in her channel, including both short and long videos on this subject. Her videos are great for learning the basics. Her free videos won’t teach you everything you need to know for the CKA or CKAD certifications, but they will give you a good baseline.

Personally I used KodeKloud’s courses for the majority of my learning. However when I wanted to reinforce certain concepts, I often watched Nana’s videos on them to hear them explained in a different way. This was very helpful. Nana explains complex concepts in a very clear way.

Kubernetes Fundamentals (LFS258)

Link: Linux Foundation - Training

This is the Kubernetes course that is recommended in the “official” learning path by the Linux Foundation. Although it is not a cheap course, it can be bundled together with a purchase of a CKA exam voucher, which can make it affordable when bought during one of their frequent sales (such as Cyber Monday).

The course videos cover all the relevant Kubernetes topics. In terms of labs, you don’t get practice labs like with KodeKloud, instead you are provided instructions for setting up a Kubernetes environment either locally or using a cloud provider (AWS or GCP). Using a cloud provider for all the labs could potentially get expensive though.

Each section starts with videos, continues with lab exercises and ends with a Knowledge Check. The lab exercises have to be run on your own cluster. The Knowledge Check is an interactive quiz testing your knowledge.

Overall this course isn’t bad but I personally think it’s hard to recommend it when comparing it to KodeKloud… Especially for its full price (which is more expensive than KodeKloud’s courses). If you can get in a bundle during a sale then it might be worth it for you, just remember that you will still have to set up your own cluster.

Certified Kubernetes Administrator CKA Video Course by Sander van Vugt

Link: sandervanvugt.com

I have not tried this course personally, however my coworker Lior Dux highly recommends it.