Certified Kubernetes Administrator (CKA) Study Guide (Benjamin Muschko) (z-library.sk, 1lib.sk, z-lib.sk)

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Benjamin Muschko In-Depth Guidance and Practice Certif ied Kubernetes Administrator (CKA) Study Guide 2nd Edition

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ISBN: 979-8-341-60840-5 US $69.99 CAN $87.99 KUBERNETES The ability to administer and monitor a Kubernetes cluster is in high demand. Those who want to demonstrate their credibility and value in the job market hold the Cloud Native Computing Foundation’s Certified Kubernetes Administrator (CKA) certification—proving they can confidently work in a Kubernetes environment. The CKA certification exam isn’t the typical multiple-choice format of other professional certifications. Instead, it’s performance-based, requiring deep knowledge of the tasks under immense time pressure. And the CKA was overhauled in 2025, with an updated curriculum covering new topics including Custom Resource Definitions (CRDs) and Operators, the Gateway API, and more. This updated study guide takes you through all the competencies covered in the exam, including new sections reflecting the recent changes. Author Benjamin Muschko also shares his personal experience with preparing for all aspects of the exam. • Learn when and how to apply Kubernetes concepts to administer and troubleshoot a production-grade cluster • Understand the objectives, abilities, and tips and tricks needed to pass the CKA exam • Explore the ins and outs of the kubectl command-line tool • Demonstrate competency to perform the responsibilities of a Kubernetes administrator • Solve real-world Kubernetes problems in a hands-on command-line environment • Effectively navigate and solve questions during the CKA exam Certified Kubernetes Administrator (CKA) Study Guide “There are many things to learn with Kubernetes, and you can get distracted with interesting tangents. Benjamin Muschko nails it in this guide to keep you focused on the important features needed to ace your certification.” Jonathan Johnson, independent software architect “Certified Kubernetes Administrator (CKA) Study Guide is a beautifully concise look at the technical skills needed to pass the Certified Kubernetes Administrator exam.” Kaslin Fields, CNCF Ambassador, developer advocate at Google Benjamin Muschko is a software engineer, consultant, and trainer with more than 20 years of experience in the industry. He specializes in cloud native application development and transformation, container solutions, DevSecOps, and continuous integration/continuous delivery implementations. Ben is an author, conference speaker, and open source advocate.

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Benjamin Muschko Certified Kubernetes Administrator (CKA) Study Guide In-Depth Guidance and Practice SECOND EDITION

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979-8-341-60840-5 [LSI] Certified Kubernetes Administrator (CKA) Study Guide by Benjamin Muschko Copyright © 2026 Automated Ascent LLC. All rights reserved. Published by O’Reilly Media, Inc., 141 Stony Circle, Suite 195, Santa Rosa, CA 95401. O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are also available for most titles (http://oreilly.com). For more information, contact our corporate/institutional sales department: 800-998-9938 or corporate@oreilly.com. Acquisitions Editor: Megan Laddusaw Development Editor: Corbin Collins Production Editor: Beth Kelly Copyeditor: Miah Sandvik Proofreader: Emily Wydeven Indexer: Potomac Indexing, LLC Cover Designer: Susan Thompson Cover Illustrator: Karen Montgomery Interior Designer: David Futato Interior Illustrator: Kate Dullea June 2022: First Edition January 2026: Second Edition Revision History for the Second Edition 2026-01-14: First Release See http://oreilly.com/catalog/errata.csp?isbn=9798341608405 for release details. The O’Reilly logo is a registered trademark of O’Reilly Media, Inc. Certified Kubernetes Administrator (CKA) Study Guide, the cover image, and related trade dress are trademarks of O’Reilly Media, Inc. The views expressed in this work are those of the author and do not represent the publisher’s views. While the publisher and the author have used good faith efforts to ensure that the information and instructions contained in this work are accurate, the publisher and the author disclaim all responsibility for errors or omissions, including without limitation responsibility for damages resulting from the use of or reliance on this work. Use of the information and instructions contained in this work is at your own risk. If any code samples or other technology this work contains or describes is subject to open source licenses or the intellectual property rights of others, it is your responsibility to ensure that your use thereof complies with such licenses and/or rights.

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Table of Contents Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii Part I. Introduction 1. Exam Details and Resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Kubernetes Certification Learning Path 3 Kubernetes and Cloud Native Associate (KCNA) 4 Kubernetes and Cloud Native Security Associate (KCSA) 4 Certified Kubernetes Application Developer (CKAD) 4 Certified Kubernetes Administrator (CKA) 5 Certified Kubernetes Security Specialist (CKS) 5 Exam Objectives 5 Curriculum 6 Cluster Architecture, Installation, and Configuration 6 Workloads and Scheduling 6 Servicing and Networking 7 Storage 7 Troubleshooting 7 Involved Kubernetes Primitives 7 Documentation 8 Exam Environment and Tips 9 Candidate Skills 10 Time Management 11 Command-Line Tips and Tricks 11 Setting a Context and Namespace 12 Using the Alias for kubectl 12 Using kubectl Command Auto-Completion 12 iii

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Internalizing Resource Short Names 12 Practicing and Practice Exams 13 Summary 14 2. Kubernetes in a Nutshell. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 What Is Kubernetes? 15 Features 16 High-Level Architecture 16 Control Plane Node Components 18 Common Node Components 18 Advantages 19 Summary 20 3. Interacting with Kubernetes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 API Primitives and Objects 21 Using kubectl 23 Managing Objects 24 Imperative Object Management 24 Declarative Object Management 26 Hybrid Approach 29 Which Approach to Use? 29 Summary 30 Part II. Cluster Architecture, Installation, and Configuration 4. Cluster Installation and Upgrade. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Provisioning the Infrastructure 33 Understanding Extension Interfaces 34 Container Network Interface (CNI) 34 Container Runtime Interface (CRI) 34 Container Storage Interface (CSI) 35 Using kubeadm 35 Installing a Cluster 35 Initializing the Control Plane Node 36 Installing a Pod Network Add-on 38 Joining the Worker Nodes 39 Managing a Highly Available Cluster 40 Stacked etcd Topology 41 External etcd Node Topology 41 Upgrading a Cluster Version 42 iv | Table of Contents

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Upgrading Control Plane Nodes 44 Upgrading Worker Nodes 46 Summary 48 Exam Essentials 48 Sample Exercises 49 5. Backing Up and Restoring etcd. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Using the etcd Administration Utilities 51 Backing Up etcd 52 Restoring etcd 54 Summary 55 Exam Essentials 55 Sample Exercises 56 6. Authentication, Authorization, and Admission Control. . . . . . . . . . . . . . . . . . . . . . . . . . 57 Processing an API Request 57 Authentication with kubectl 58 The Kubeconfig 58 Managing Kubeconfig Using kubectl 60 Authorization with Role-Based Access Control 61 RBAC Overview 61 Understanding RBAC API Primitives 62 Default User-Facing Roles 63 Creating Roles 63 Listing Roles 65 Rendering Role Details 65 Creating RoleBindings 65 Listing RoleBindings 66 Rendering RoleBinding Details 66 Seeing the RBAC Rules in Effect 67 Namespace-Wide and Cluster-Wide RBAC 68 Aggregating RBAC Rules 68 Working with Service Accounts 70 The Default Service Account 70 Creating a Service Account 71 Setting Permissions for a Service Account 71 Admission Control 76 Summary 76 Exam Essentials 77 Sample Exercises 77 Table of Contents | v

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7. Operators and Custom Resource Definitions (CRDs). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 Working with Operators 79 The Operator Pattern 80 Discovering Operators 80 Installing Operators 82 Working with Custom Resource Definitions 83 Discovering CRDs 83 Instantiating a CR for one of the CRDs 84 Interacting with a CR 85 Inspecting the Controller 85 Summary 86 Exam Essentials 86 Sample Exercises 87 8. Helm and Kustomize. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 Working with Helm 90 Managing an Existing Chart 90 Identifying a Chart 91 Adding a Chart Repository 92 Searching for a Chart in a Repository 94 Installing a Chart 94 Listing Installed Charts 96 Upgrading an Installed Chart 96 Uninstalling a Chart 97 Working with Kustomize 97 Composing Manifests 98 Generating Manifests from Other Sources 99 Adding Common Configuration Across Multiple Manifests 101 Customizing a Collection of Manifests 103 Key Differences Between Helm and Kustomize 105 Summary 106 Exam Essentials 106 Sample Exercises 107 Part III. Workloads and Scheduling 9. Pods and Namespaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 Working with Pods 112 Creating Pods 112 Listing Pods 114 vi | Table of Contents

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Pod Lifecycle Phases 114 Container-Level Restarts 115 Rendering Pod Details 116 Accessing Logs of a Pod 117 Executing a Command in Container 117 Creating a Temporary Pod 118 Using a Pod’s IP Address for Network Communication 118 Configuring Pods 119 Deleting a Pod 122 Working with Namespaces 122 Listing Namespaces 123 Creating and Using a Namespace 123 Setting a Namespace Preference 124 Deleting a Namespace 124 Summary 124 Exam Essentials 125 Sample Exercises 125 10. ConfigMaps and Secrets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Working with ConfigMaps 128 Creating a ConfigMap 128 Consuming a ConfigMap as Environment Variables 130 Mounting a ConfigMap as a Volume 130 Working with Secrets 132 Creating a Secret 133 Consuming a Secret as Environment Variables 136 Remapping Environment Variable Keys 137 Mounting a Secret as a Volume 138 Summary 139 Exam Essentials 139 Sample Exercises 140 11. Deployments and ReplicaSets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 Working with Deployments 141 Creating Deployments 142 Listing Deployments, ReplicaSets, and Their Pods 144 Rendering Deployment Details 145 Replica Replacement 146 Deleting a Deployment 147 Performing Rolling Updates and Rollbacks 148 Updating a Deployment’s Pod Template 148 Table of Contents | vii

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Rolling Out a New Revision 149 Adding a Change Cause for a Revision 151 Rolling Back to a Previous Revision 151 Summary 152 Exam Essentials 152 Sample Exercises 153 12. Scaling Workloads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 Manual Scaling of Workload 156 Manually Scaling a Deployment 156 Manually Scaling a StatefulSet 156 Autoscaling of Workload 158 Prerequisites for Autoscaling 159 Creating Horizontal Pod Autoscalers 159 Listing Horizontal Pod Autoscalers 161 Rendering Horizontal Pod Autoscaler Details 161 Defining Multiple Scaling Metrics 162 Summary 163 Exam Essentials 164 Sample Exercises 164 13. Resource Requirements, Limits, and Quotas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Working with Resource Requirements 166 Defining Container Resource Requests 166 Defining Container Resource Limits 167 Defining Container Resource Requests and Limits 168 Working with Resource Quotas 170 Creating ResourceQuotas 170 Rendering ResourceQuota Details 171 Exploring a ResourceQuota’s Runtime Behavior 171 Working with Limit Ranges 173 Creating LimitRanges 174 Rendering LimitRange Details 175 Exploring a LimitRange’s Runtime Behavior 175 Summary 177 Exam Essentials 178 Sample Exercises 178 14. Pod Scheduling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 Pod Scheduling Algorithm 181 Setting Up a Multi-Node Development Cluster 182 viii | Table of Contents

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Determining the Node a Pod Runs On 183 Pod Scheduling Options 183 Working with Node Selectors 184 Labeling a Node 184 Assigning a Node Selector to a Pod 185 Working with Node Affinity and Anti-Affinity 186 Assigning a Node Affinity to a Pod 186 Node Affinity Types 187 Node Affinity Operators 188 Assigning a Node Anti-Affinity to a Pod 188 Working with Taints and Tolerations 189 Tainting a Node 190 Taint Effects 191 Assigning a Toleration to a Pod 191 Working with Pod Topology Spread Constraints 192 Assigning a Topology Spread Constraint to a Pod 192 Topology Spread Constraint Effects at Runtime 193 Summary 193 Exam Essentials 194 Sample Exercises 194 Part IV. Storage 15. Volumes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 Purpose of Volumes 198 Volume Types 198 Creating and Accessing Volumes 199 Read-Only Volume Mounts 200 Summary 201 Exam Essentials 201 Sample Exercises 201 16. Persistent Volumes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 Working with Persistent Volumes 204 Volume Types 204 Static Versus Dynamic Provisioning 205 Creating PersistentVolumes 205 Configuration Options for a PersistentVolume 206 Volume Mode 206 Access Mode 207 Table of Contents | ix

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Reclaim Policy 208 Node Affinity 208 Creating PersistentVolumeClaims 210 Binding by Volume Name 211 Mounting PersistentVolumeClaims in a Pod 212 Storage Classes 213 Creating Storage Classes 214 Using Storage Classes 215 Summary 216 Exam Essentials 216 Sample Exercises 216 Part V. Servicing and Networking 17. Services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 Working with Services 222 Service Types 223 Port Mapping 224 Creating Services 225 Listing Services 227 Rendering Service Details 227 The ClusterIP Service Type 228 Creating and Inspecting the Service 229 Accessing the Service 230 The NodePort Service Type 232 Creating and Inspecting the Service 233 Accessing the Service 234 The LoadBalancer Service Type 234 Creating and Inspecting the Service 235 Accessing the Service 236 Summary 237 Exam Essentials 237 Sample Exercises 237 18. Ingresses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 Working with Ingresses 240 Installing an Ingress Controller 240 Deploying Multiple Ingress Controllers 241 Configuring Ingress Rules 242 Creating Ingresses 242 x | Table of Contents

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Defining Path Types 244 Listing Ingresses 244 Rendering Ingress Details 244 Accessing an Ingress 246 Summary 247 Exam Essentials 247 Sample Exercises 248 19. Gateway API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Why Is the Ingress Primitive Not Sufficient? 249 Working with the Gateway API 250 Gateway API Resources 250 Installing the Gateway API CRDs 252 Deploying a Gateway Controller 252 Creating GatewayClasses 253 Creating Gateways 254 Creating HTTPRoutes 254 Accessing the Gateway 255 Ingress to Gateway API Migration 256 Summary 257 Exam Essentials 257 Sample Exercises 257 20. Network Policies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 Working with Network Policies 259 Installing a Network Policy Controller 260 Creating a Network Policy 260 Listing Network Policies 263 Rendering Network Policy Details 264 Applying Default Network Policies 264 Restricting Access to Specific Ports 266 Summary 267 Exam Essentials 267 Sample Exercises 268 Part VI. Troubleshooting 21. Troubleshooting Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 Troubleshooting Pods 271 Retrieving High-Level Information 272 Table of Contents | xi

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Inspecting Events 272 Using Port Forwarding 274 Troubleshooting Containers 275 Inspecting Logs 275 Opening an Interactive Shell 276 Interacting with a Distroless Container 277 Troubleshooting Services and Networking 278 Diagnosing Service-to-Pod Label Selection 278 Diagnosing Service-to-Pod Port Mapping 279 Inspecting the Service’s Endpoints 279 Verifying Accessibility Scope 279 DNS Resolution Problems 280 Network Policy Restrictions 280 Inspecting Resource Metrics 281 Summary 282 Exam Essentials 283 Sample Exercises 284 22. Troubleshooting Clusters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 Inspecting the Status of Cluster Nodes 287 Inspecting the Status of Cluster Components 288 Troubleshooting Node Issues 289 Rendering Cluster Information 290 Node Showing NotReady Status 290 Checking Available Resources 291 Checking the kubelet Process 292 Checking Certificate Validity 293 Checking the kube-proxy Pod 294 Summary 294 Exam Essentials 295 Sample Exercises 295 A. Answers to Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297 B. Exam Review Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355 Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359 xii | Table of Contents

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Preface Kubernetes has become the de facto standard for container orchestration, with over 96% of organizations using or evaluating Kubernetes according to the CNCF Annual Survey 2023. As organizations increasingly adopt cloud native technologies, the demand for skilled Kubernetes administrators has skyrocketed. The ability to deploy, manage, troubleshoot, and secure Kubernetes clusters is now a critical skill for infra‐ structure engineers, DevOps professionals, and system administrators worldwide. To provide a standardized way to validate these essential skills, the Cloud Native Computing Foundation (CNCF), in collaboration with the Linux Foundation, created the Certified Kubernetes Administrator (CKA) program. Since its launch in 2017, the CKA has become one of the most sought-after certifications in the industry. Accord‐ ing to the CNCF Annual Report 2024, over 250,000 professionals have earned CNCF certifications, with the Kubernetes certifications representing the majority of this ach‐ ievement. The report also highlights that the Kubestronaut program, which recog‐ nizes professionals who earn all Kubernetes certifications, reached 1,500 members in its first year alone, demonstrating the strong commitment to comprehensive Kuber‐ netes expertise. The CKA certification validates that you have the skills, knowledge, and competency to perform the responsibilities of a Kubernetes administrator. Unlike traditional multiple-choice exams, the CKA is a rigorous, performance-based test that requires you to solve real-world problems in a live Kubernetes environment under time pres‐ sure. With a pass rate historically hovering around 60%, earning this certification demonstrates genuine, hands-on expertise that employers value. This study guide will prepare you to pass the CKA certification exam by covering all topics in the curriculum. We’ll explore cluster architecture, installation and configu‐ ration, workload management, networking, storage, and troubleshooting. Through‐ out this journey, you’ll gain practical experience with command-line tools like kubectl, kubeadm, and helm to learn the best practices that will serve you well both in the exam and in real-world scenarios. xiii

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Who This Book Is For This book is for system administrators, DevOps engineers, infrastructure architects, and anyone who wants to prepare for the CKA exam. While the content covers all aspects of the exam curriculum, readers should have basic knowledge of Linux, con‐ tainers, and fundamental Kubernetes concepts. If you are completely new to Kubernetes, I recommend that you first read Kubernetes: Up and Running, 3rd Edition by Brendan Burns, Joe Beda, Kelsey Hightower, and Lachlan Evenson (O’Reilly, 2022) or Kubernetes in Action by Marko Lukša (Manning Publications, 2018). The CKA should not be confused with the Certified Kubernetes Application Devel‐ oper (CKAD) exam. While there is topic overlap, the CKA focuses on cluster admin‐ istration, installation, and maintenance tasks rather than application deployment and management. For those interested in the complete Kubernetes certification path, the CNCF offers a certification bundle that includes CKA, CKAD, and CKS (Certified Kubernetes Security Specialist). In addition to the Kubernetes-specific certifications, the CNCF offers complimentary certifications that validate expertise in cloud native technologies. These industry- recognized certifications also include project-specific options like Prometheus Certi‐ fied Associate (PCA) and GitOps Certified Associate (CGOA), all featuring hands-on, performance-based exams in command-line environments. What You Will Learn The content of this book follows the official CKA exam curriculum, covering cluster architecture, installation and configuration, workload management, networking, storage, and troubleshooting. Given the breadth of Kubernetes functionality, it’s impossible to cover every configuration option without duplicating the official docu‐ mentation. Test takers are encouraged to reference the Kubernetes documentation during the exam, as it’s an allowed resource. Practical experience is crucial for passing the exam. Each chapter contains a “Sample Exercises” section with practice questions that mirror the exam format. Solutions to these exercises are available in Appendix A. What’s New in the Second Edition The CNCF regularly updates the CKA curriculum to keep pace with Kubernetes evo‐ lution and industry needs. The curriculum update effective February 18, 2025, brings significant changes that reflect how Kubernetes is actually used in production envi‐ ronments today. The exam now uses Kubernetes v1.33, and this second edition has xiv | Preface

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been completely updated to cover all the new topics while removing outdated content. Based on the official program changes and CNCF announcements, the next sections list the topics added and removed. Topics Added Gateway API A major addition to the curriculum, the Gateway API represents the future of ingress traffic management in Kubernetes. This modern alternative to traditional Ingress resources provides more expressive routing rules, better multitenancy support, and extensible traffic management capabilities. You’ll learn how to implement and manage Gateway resources, HTTPRoutes, and GatewayClasses. Helm Package management with Helm is now part of the CKA curriculum. You’ll need to understand how to use Helm for deploying applications, managing releases, and working with Helm charts. This reflects the reality that Helm has become the de facto standard for Kubernetes application packaging. Kustomize Declarative configuration management using Kustomize is now required knowl‐ edge. The curriculum covers how to use Kustomize for managing environment- specific configurations without templating, a critical skill for managing applications across multiple environments. Custom Resource Definitions (CRDs) and operators Understanding how to extend Kubernetes through CRDs and work with opera‐ tors is now essential. This addition reflects the widespread adoption of the opera‐ tor pattern in production Kubernetes environments. Container Runtime Interfaces The curriculum now includes coverage of extension interfaces like Container Network Interface (CNI), Container Storage Interface (CSI), and Container Run‐ time Interface (CRI). Understanding these interfaces is crucial for troubleshoot‐ ing and configuring production clusters. Expanded CoreDNS coverage While DNS was always part of the curriculum, there’s now expanded focus on CoreDNS configuration, troubleshooting DNS issues, and understanding service discovery mechanics in detail. Network policies Network policies are now explicitly mentioned in the curriculum. You’ll need to understand how to define and enforce network policies to control traffic flow Preface | xv

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between Pods, namespaces, and external endpoints. This addition emphasizes the growing importance of network segmentation and security in multitenant clusters. Pod admission and scheduling The topic “Configure Pod admission and scheduling” has been made more prominent in the curriculum. This includes deeper coverage of scheduling mech‐ anisms, node affinity, taints and tolerations, Pod priority and preemption, and admission controllers. The increased emphasis reflects the complexity of work‐ load placement in production clusters. Topics Removed The competency “Provision underlying infrastructure to deploy a Kubernetes cluster” has been removed, acknowledging that most organizations now use managed Kuber‐ netes platforms rather than provisioning infrastructure from scratch. Structural Changes While the five main domains (Cluster Architecture, Installation and Configuration; Workloads and Scheduling; Services and Networking; Storage; and Troubleshooting) remain the same, the competencies within each domain have been updated to reflect modern practices. The exam continues to be performance-based with a 2-hour time limit, but the sce‐ narios now better reflect real-world tasks that administrators face when managing production Kubernetes clusters. Additionally, I’ve included an “Exam Review Guide” in Appendix B that maps all curriculum topics to corresponding chapters and pro‐ vides quick reference links to the Kubernetes documentation. Conventions Used in This Book The following typographical conventions are used in this book: Italic Indicates new terms, URLs, email addresses, filenames, and file extensions. Constant width Used for program listings, as well as within paragraphs to refer to program ele‐ ments such as variable or function names, databases, data types, environment variables, statements, and keywords. Constant width bold Shows commands or other text that should be typed literally by the user. xvi | Preface

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Constant width italic Shows text that should be replaced with user-supplied values or by values deter‐ mined by context. This element signifies a tip or suggestion. This element signifies a general note. This element indicates a warning or caution. Using Code Examples The source code for all examples and exercises in this book is available on GitHub. The repository is distributed under the Apache License 2.0. The code is free to use in commercial and open source projects. If you encounter an issue in the source code or if you have a question, open an issue in the GitHub issue tracker. I’m happy to have a conversation and fix any issues that might arise. This book is here to help you get your job done. In general, if example code is offered with this book, you may use it in your programs and documentation. You do not need to contact us for permission unless you’re reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing examples from O’Reilly books does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product’s documentation does require permission. We appreciate, but generally do not require, attribution. An attribution usually includes the title, author, publisher, and ISBN. For example: “Certified Kubernetes Administrator (CKA) Study Guide, by Benjamin Muschko (O’Reilly). Copyright 2026 Automated Ascent, LLC, 979-8-341-60840-5.” Preface | xvii

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If you feel your use of code examples falls outside fair use or the permission given above, feel free to contact us at permissions@oreilly.com. O’Reilly Online Learning For more than 40 years, O’Reilly Media has provided technol‐ ogy and business training, knowledge, and insight to help companies succeed. Our unique network of experts and innovators share their knowledge and expertise through books, articles, and our online learning platform. O’Reilly’s online learning platform gives you on-demand access to live training courses, in-depth learning paths, interactive coding environments, and a vast collection of text and video from O’Reilly and 200+ other publishers. For more information, visit https://oreilly.com. How to Contact Us Please address comments and questions concerning this book to the publisher: O’Reilly Media, Inc. 141 Stony Circle, Suite 195 Santa Rosa, CA 95401 800-889-8969 (in the United States or Canada) 707-827-7019 (international or local) 707-829-0104 (fax) support@oreilly.com https://oreilly.com/about/contact.html We have a web page for this book, where we list errata, examples, and any additional information. You can access this page at https://oreil.ly/cka-2ed. For news and information about our books and courses, visit https://oreilly.com. Find us on LinkedIn: https://linkedin.com/company/oreilly-media. Watch us on YouTube: https://youtube.com/oreillymedia. Follow the author on GitHub: https://github.com/bmuschko. Follow the author’s blog: https://bmuschko.com. Acknowledgments Every book project is a long journey and would not be possible without the help of the editorial staff and technical reviewers. Special thanks go to Werner Dijkerman, xviii | Preface