Certified Kubernetes Administrator Course

The Certified Kubernetes Administrator (CKA) exam tests practical skills for administering Kubernetes clusters. It is a hands-on exam where candidates complete tasks in a real cluster instead of answering theory questions. The exam covers cluster architecture, installation and configuration, workloads and scheduling, services and networking, storage, security, and troubleshooting. A good study path starts with control plane and node components, then kubeadm installation, workloads and controllers, services and ingress, persistent storage, RBAC and NetworkPolicies, and finally kubectl troubleshooting. You should practice with minikube, kind, or kubeadm and get comfortable with kubectl commands. This course follows the exam domains and links to a practice bank with 60 original questions to help you review key concepts before the hands-on exam.

A Kubernetes cluster has a control plane and worker nodes. The control plane includes kube-apiserver, kube-scheduler, kube-controller-manager, and etcd. The API server is the front end for all cluster management. etcd stores cluster state, the scheduler places pods on nodes, and controllers maintain desired states. Worker nodes run kubelet, kube-proxy, and a container runtime. kubeadm is the common tool for bootstrapping clusters, and kubectl is the command-line client. A kubeconfig file stores clusters, users, and contexts so kubectl can connect. Namespaces divide cluster resources for isolation. Understanding these components helps you troubleshoot installation and connectivity issues in the exam.

Pods are the smallest deployable units and can contain one or more containers. Deployments manage stateless applications with rollouts and scaling, StatefulSets provide stable identity and storage for stateful apps, DaemonSets run a pod on every node, Jobs run tasks to completion, and CronJobs run jobs on a schedule. ReplicaSets maintain a desired number of replicas. Scheduling is influenced by nodeSelector, node affinity, pod affinity, taints, and tolerations. Resource requests guarantee minimum capacity, and limits cap usage. Liveness probes restart unhealthy containers, and readiness probes control traffic. HorizontalPodAutoscaler scales replicas based on metrics. Practice writing manifests for each controller type because the exam includes hands-on object creation.

Services give pods stable network identity. ClusterIP is the default internal Service, NodePort exposes a port on every node, LoadBalancer provisions a cloud load balancer, and a headless Service returns pod IPs directly. Ingress routes HTTP and HTTPS traffic to Services. CoreDNS resolves Service names as service.namespace.svc.cluster.local. CNI plugins such as Calico implement pod networking. Storage uses PersistentVolumes, PersistentVolumeClaims, and StorageClasses. A PVC requests storage and binds to a PV, while a StorageClass enables dynamic provisioning. ConfigMaps hold non-sensitive config and Secrets hold sensitive data. Understanding these resources helps you expose applications and persist data in exam tasks.

Kubernetes security uses RBAC, ServiceAccounts, securityContext, Secrets, and NetworkPolicies. Role and ClusterRole define permissions, and RoleBinding and ClusterRoleBinding grant them to users or ServiceAccounts. securityContext can drop capabilities, set user IDs, and enforce read-only filesystems. NetworkPolicies control pod-to-pod traffic. Troubleshooting relies on kubectl: get, describe, logs, events, exec, top, and drain. kubectl get shows resources, describe gives details and events, logs prints container logs, exec runs commands in containers, top shows usage, and drain evicts pods for maintenance. For the exam, work through tasks step by step, verify with kubectl get after each change, and keep manifests ready to apply. Review the linked question bank and read explanations for every mistake.