10 steps for achieving the CKA certification

There are always new technologies that are well-spoken or that are on Hype, some are here to stay and others are short-lived, Kubernetes, as well as Docker, are examples of technologies that are in love with hipsters and technology enthusiasts. That is why it is very important to stay tuned in technologies that are in high demand in the market and try to update your skills to keep up with the technology changes in the area and not be out of date in the market. As I said earlier, Kubernetes has a big movement in the technology area, so thinking about updating I decide to study and take the Kubernetes certification exam because this tool is very required in the actual technology’ s scenario, I’ll try to describe in this post tips and the way to achieve the CKA certification.

The Kubernetes certification is maintained by CNCF (Cloud Native Computing Foundation).

The Exam is scheduled on CNCF site, at this date the appointment costs $300 and you have a retake if you don’t pass, the exam is online.

You need to understand the concepts, because you do not need to memorize all the documentation or even commands, a differential that makes taking the exam easier is the access to the Kubernetes documentation which is allowed at the time of the exam, so you need to at least have a conceptual understanding of what it is for each component of Kubernetes and which path to follow to configure it, knowing the way you can search about in the documentation and check what are the configuration commands necessary to achieve what the question requires.

Requirements to be comfortable on your study journey is:

• We need to know about how containers works
• We need to understand concepts and basics about Network, Servers, Services, DNS, SSH, Bash, Linux, Cloud Concepts
• Knowledge of the YAML language

Links about certification

• Certified Kubernetes Administrator: https://www.cncf.io/certification/cka/
• Exam Curriculum (Topics): https://github.com/cncf/curriculum
• Candidate Handbook: https://www.cncf.io/certification/candidate-handbook
• Exam Tips: http://training.linuxfoundation.org/go//Important-Tips-CKA-CKAD
• Kubernetes documentation: https://kubernetes.io/docs/home/

1. Create a study plan

• You need to create an agenda and determinate how much hours per week you can study to achieve your goal
• Organize the study agenda, 6 hours per week is a good time to study and not interfere on your other tasks, depends on your agenda, the more weekly study time you have, the faster the route to the exam will be
• if you want to pass, take the study schedule very seriously because by studying the topics listed on the next topic, you will be able to take the exam without much headache
• Increase the study time a few days before the exam, this strategy is better for you to review topics and accumulate experience without the risk of forgetting the topics along the time
• Try to study at times that you will not be disturbed, times that avoid external interference and loss of focus. I prefer to study in the morning because it is a time that I can absorb more and I did not go through the stress of the day
• I have listed some study plan tips but not all people study and learn the same way, build your study plan according to your needs and your goal of taking the exam, remember that an effort is necessary and having the commitment
• If you want to buy a course, I recommend the course Certified Kubernetes Administrator (CKA) with Practice Tests on Udemy platform, this course covers all topics

2. Study the exam topics

I described below the exam topics, weights, and a brief description, links, and tricks for the principal concepts that you need to study to achieving CKA:

1. Core Concepts 19%

• Cluster Architecture
• ETCD Basic concepts
• Kube API Server
• Kube Controller Manager
• Kube Scheduler
• Kubelet
• Kube Proxy
• Pods
• ReplicaSets
• Deployments
• Namespaces
• Services
• Kubectl command

2. Installation, Configuration & Validation 12%

• Install Kubernetes using kubeadm
• Install Kubernetes using the Hardway mode (optional but recommended to learn)
• Tests the cluster, analyze

3. Application Lifecycle Management 8%

• Rolling Updates and Rollbacks
• Commands and arguments
• Configmaps
• Secrets
• Scale
• Multi Container
• Init containers

4. Networking 11%

• Understand Switching and Routing concepts
• DNS Concepts
• CoreDNS
• Network Namespaces
• Docker Networking
• CNI
• Ingress

5. Scheduling 5%

• Manual Scheduling
• Labels and Selectors
• Taints and Tolerations
• Node Selectors
• Node Affinity
• Resource Limits
• DaemonSets
• Static Pods

6. Security 12%

• TLS Basics and Certificates
• Authentication
• kubeconfig
• API Groups
• RBAC
• Cluster Roles and Role Bindings
• Security Contexts
• Network Policy

7. Logging / Monitoring 5%

• Monitor cluster components
• Application Logs
• kubectl top command

8. Storage 7%

• Understand storage in docker
• Volumes
• PV (Persistent Volumes)
• PVC (Persistent Volume Claims)
• Configure PVC on applications

9. Cluster Maintenance 11%

• OS Upgrades
• Cluster Upgrade Process
• Backup and Restore
• ETCDCTL command

10. Troubleshooting 10%

• Application failure
• Control Plane Failure
• Worker Node failure
• Network issues

11. Other

• JSON Path
• Kubectl advanced

3. Install Kubernetes and create an environment for study

• We need to create a minimum a cluster with 3 nodes (1 master and 2 worker nodes) to tests and run commands and examples
• You can use a Cloud Provider (AWS. GCP, Azure) to create a remote environment or any virtualized software (VirtualBox, VMWare workstation) to create a local environment on your machine
• This step is very important to simulate the documentation examples and understand about Kubernetes
• You need to install kubernetes using the kubeadm
• You can install using the hard way mode to understand better all components and how these works
• This environment will be used when you’ve read the docs and simulate and run the examples

4. Run the examples and simulate troubleshooting scenarios on this environment created before

• Run the documentation examples about all topics listed on step 2 of this post.
• Simulate errors and problems on this environment to understand how you can solve problems on the applications or in the cluster

5. Do exam mocks

• https://github.com/alijahnas/CKA-practice-exercises
• https://github.com/stretchcloud/cka-lab-practice
• https://medium.com/bb-tutorials-and-thoughts/practice-enough-with-these-questions-for-the-ckad-exam-2f42d1228552
• On the internet has a lot of mock exams paid, you can buy one of these exams to training your knowledge. But if you don’t want to spend your money, you can found examples of the exam questions available on Github and blogs for free

6. Schedule the exam

• The cost is $300 and includes one free retake.
• Look for discount coupons or if the CNCF has any promotions/exam vouchers before you schedule. You can save your money.
• I scheduled the exam for a monday morning, so I had a weekend to review the topics and focus on the subjects that had the most difficulty.
• I scheduled the exam before starting the study, that way I was forced to study and fulfill the goal, it worked for me, but you should make this decision

7. Understand the Exam

• The exam has 24 questions and you have 3 hours to finalize
• The questions are hands-on, you have a shell to execute the commands and you need to save commands outputs some times
• Pay attention to the time for complete, because if you have difficulty on any question, mark the question for review and skip to return posteriorly
• You need to install a chrome extension recommended by the exam provider
• Close all windows, leave only the navigator window on the exam page and another tab on the documentation page
• You cannot use headphones or any devices, just the computer that you access the exam site and Kubernetes documentation, your desk needs to be clean, at the time of the exam a chat is opened and a person checks these points together with you, your screen is shared at the time of the exam, that person from the exam center will pass all instructions by chat
• Pay attention to the k8s contexts, because the exam has a lot of contexts, for each question the context will be specified, take a look at this point.

8. Review the topics that you have more difficulty

• Review the topics that you have more difficulty and have the highest weight
• Execute commands and create objects in the kubernetes to memorize

9. Keep Calm

• Stay calm, plan a way to quickly search the documentation, memorize keywords and topics in the documentation to make it easier to search on the day of the exam
• The exam is not so complicated but it takes time, stays calm, by having the documentation you can do anything related to Kubernetes, it is important to know the paths and have knowledge of the operation to be more accurate in the research

10. Do the Exam

• Since the exam requires concentrated effort for 3 hours and is straining both physically and mentally, I’d the advice to schedule the exam during morning hours.
• Create multiples alias on the exam bash: e.q: # alias kl=kubectl logs or #alias kg=kubectl get, using alias you can save your time, is better to type less.
• Pay attention to the exam time, if you are wasting a lot of time on an issue check for review and skip to the next question
• You can have a bottle of water on your desk, as long as it has no labels and is transparent
• The exam result is sent within 72 hours of completion.