If you’re preparing for the Certified Kubernetes Administrator (CKA) exam, you might be feeling a bit overwhelmed with the breadth of topics. However, with the right approach and consistent practice, you can pass the CKA with flying colors. I’m thrilled to share that I passed the CKA on my first attempt with a 96/100 score. Here’s my experience and the key areas that I focused on, along with some tips and tricks that helped me nail the exam.
- Practice, Practice, Practice
- Copy paste from documentation
- Use imperative Commands where ever possible
The Important Questions: etcd Backup & Restore and Node Upgrade
Two critical areas that stood out during the exam were etcd backup and restore and the node upgrade process. These tasks are essential in real-world Kubernetes administration, and the exam tests them thoroughly. Here’s how I tackled these topics:
1. etcd Backup & Restore
Being able to perform an etcd backup and restore is vital for cluster recovery. Practicing this until you can do it swiftly is important. Know the exact commands, paths, and how to restore from a backup under different failure scenarios.
2. Node Upgrade
Upgrading a Kubernetes node was the most important question in my exam. Here are some tips for mastering it:
- Practice repeatedly until you can upgrade a node in under 7 minutes. Trust me, with 4–5 practices and little understanding, I managed to complete it with ease.
- Make sure to document and familiarise yourself with the necessary steps.
Here’s a step-by-step guide for upgrading a control plane and worker node:
Steps to Upgrade the Control Plane:
# Drain the control plane
k drain controlplane --ignore-daemonsets
# Update the Kubernetes package source list
vi /etc/apt/sources.list.d/kubernetes.list
apt update
# Find the required kubeadm version
sudo apt-cache madison kubeadm
# Install the specific kubeadm version
sudo apt-get install -y kubeadm='1.30.0-1.1'
# Plan the upgrade
kubeadm upgrade plan v1.30.0-1.1
# Apply the upgrade
kubeadm upgrade apply v1.30.0
# Find and install the corresponding kubelet version
apt-cache madison kubelet
apt install kubelet=1.30.0-1.1
# Restart the kubelet service
systemctl restart kubelet.service
# Uncordon the control plane to bring it back into the cluster
k uncordon controlplaneSteps to Upgrade Worker Nodes:
# Drain the worker node
k drain node01 --ignore-daemonsets
# Update the Kubernetes package source list on the worker node
vi /etc/apt/sources.list.d/kubernetes.list
apt update
# Install kubeadm on the worker node
apt-get install -y kubeadm=1.30.0-1.1
# Upgrade the node using kubeadm
kubeadm upgrade node
# Install the corresponding kubelet version
apt install -y kubelet=1.30.0-1.1
# Reload the system daemon and restart the kubelet
systemctl daemon-reload
systemctl restart kubeletWith practice, you’ll be able to carry out these steps efficiently within a 7–8 minutes, which is crucial for scoring well in the CKA exam.
CKA Domains & Competencies
The CKA exam covers five domains, each focusing on key areas of Kubernetes administration. Here’s a breakdown of what I encountered and how I prepared for each domain:
1. Storage (10%)
- Understand storage classes and persistent volumes. use this dockumentaion page for any storage related questions it has it all pv,pvc and configured pod
- Know the difference between volume modes, access modes, and reclaim policies.
- Familiarize yourself with persistent volume claims and how to configure applications with persistent storage.
2. Troubleshooting (30%)
- This is a big chunk of the exam. You must be adept at evaluating cluster and node logging, monitoring applications, and troubleshooting issues , Practice KillerKoda Scenarios or KodeKloud mock test to master this
- Make sure you understand how to handle application failures, cluster component failures, and networking issues.
- You’ll need to manage logs (
stdoutandstderr), so practice viewing and analyzing them using tools likekubectl logs. - Use logs , events, or get -oyaml for detecting issues with resources
3. Workloads & Scheduling (15%)
- Learn how to perform rolling updates and rollbacks on deployments.
- Practice using ConfigMaps and Secrets to configure applications.
- Understand how to scale applications and manage resource limits for Pod scheduling.
- Be aware of manifest management and the common templating tools used to manage Kubernetes manifests.
4. Cluster Architecture, Installation & Configuration (25%)
- Understand Role-Based Access Control (RBAC).
- Be confident in using kubeadm to install and manage clusters.
- Practice creating highly-available clusters and deploying clusters on underlying infrastructure.
- Performing version upgrades on clusters using kubeadm is crucial (as mentioned above).
- Be prepared to implement etcd backup and restore.
5. Services & Networking (20%)
- Be well-versed in host networking configuration on cluster nodes and Pod connectivity.
- Understand different service types like ClusterIP, NodePort, and LoadBalancer, and know how to use Ingress controllers and resources.
- CoreDNS and container network interfaces (CNIs) are key concepts to master.
Final Tips
Here are a few final tips that helped me get through the CKA exam:
- Time Management: The exam is timed, so don’t spend too much time on one question. If you’re stuck, mark it and move to next and come back later.
- Practice Labs: Use platforms like Killer.sh , killerkoda , KodeKloud to simulate real exam environments. The more hands-on practice you get, the better prepared you’ll be.
- Stay Calm: The exam can be intense, but staying calm and following a systematic approach will help you manage your time and resources effectively.
