Kubernetes Expert Interview Questions
Time to find the Kubernetes Expert who will keep your container orchestration on point. This guide is loaded with interview questions carefully chosen to spot the ideal candidate. Whether it's diving into their containerization, orchestration, or cluster management expertise, these questions are structured to unveil their Kubernetes mastery.
What is the role of a Pod in Kubernetes?
Answer: A Pod is the smallest deployable unit in Kubernetes, which can contain one or more containers. Containers within the same Pod share the same IP, port space, and storage.
How do you handle persistent storage in Kubernetes?
Answer: Kubernetes provides Persistent Volumes (PVs) and Persistent Volume Claims (PVCs) for managing persistent storage resources.
Describe the difference between a Deployment and a StatefulSet.
Answer: While both are controllers, Deployments are suited for stateless applications, ensuring a specified number of replicas run. StatefulSets are for stateful applications, maintaining a sticky, unique identity for each of their Pods.
How does Kubernetes handle service discovery?
Answer: Kubernetes uses Services and DNS to enable service discovery. When a Service is created, it's assigned a unique IP and an entry is created in DNS, allowing other Pods to reach it using the service name.
What is Helm and why is it important in Kubernetes?
Answer: Helm is a package manager for Kubernetes, simplifying the deployment, configuration, and versioning of applications using charts.
How would you monitor the health of a Kubernetes cluster?
Answer: Tools like Prometheus, Grafana, and logging solutions like ELK Stack or Loki can be used to monitor and log the health and performance of a cluster.
Describe a NodePort service.
Answer: NodePort is a service type that exposes a service on a static port on each Node's IP. External traffic can access the service on that port, which then routes the traffic to the appropriate Pod.
How do you scale applications in Kubernetes?
Answer: Applications can be scaled manually using the kubectl scale command or automatically with Horizontal Pod Autoscalers based on CPU utilization or other select metrics.
What is the purpose of a ConfigMap?
Answer: ConfigMap allows separating configuration data from application code, making it possible to manage configuration data without changing the application's container image.
How does Kubernetes achieve high availability?
Answer: Kubernetes can run multiple replicas of pods, spread them across nodes, set up multi-master clusters, and use services like Load Balancers to distribute traffic, ensuring high availability.
How do you handle secrets in Kubernetes?
Answer: Kubernetes provides a 'Secrets' object to store and manage sensitive information like passwords, OAuth tokens, and SSH keys.
What is a DaemonSet?
Answer: A DaemonSet ensures that an instance of a specific pod is running on all (or selected) nodes in a cluster.
How does Kubernetes' RBAC work?
Answer: Role-Based Access Control (RBAC) in Kubernetes allows administrators to define roles with certain permissions (like read, write) and bind those roles to users or service accounts.
What are Network Policies in Kubernetes?
Answer: Network Policies are specifications of how pods are allowed to communicate with each other and other endpoints.
Describe the lifecycle of a Pod.
Answer: Pods go through phases: Pending, Running, Succeeded, Failed, and Unknown. They're created, can run tasks, complete those tasks (or fail), and then they remain until removed.
How does auto-scaling work in Kubernetes?
Answer: Kubernetes provides the Horizontal Pod Autoscaler which automatically scales the number of pods in a deployment or replica set based on observed CPU utilization or other metrics.
What is a Kubernetes Ingress?
Answer: Ingress is an API object that manages external access to services within a cluster, typically HTTP. Ingress can provide load balancing, SSL termination, and name-based virtual hosting.
What are the different types of services in Kubernetes?
Answer: ClusterIP (default), NodePort, LoadBalancer, and ExternalName.
How do you handle rolling updates in Kubernetes?
Answer: Rolling updates are managed using the Deployment controller, which incrementally updates pods with new versions, ensuring no downtime.
What is the difference between a Liveness probe and a Readiness probe?
Answer: Liveness probes check if an application within a pod is running, whereas Readiness probes determine if the application is ready to serve traffic.
How is storage provisioned in Kubernetes?
Answer: Kubernetes uses StorageClasses to define different types of storage and Dynamic Volume Provisioning to automatically create storage volumes as required.
What is the role of the kubelet?
Answer: Kubelet is an agent that runs on each node in the cluster and ensures the containers are running in a Pod.
How do you handle stateful applications in Kubernetes?
Answer: StatefulSets are used for deploying stateful applications, ensuring a specific order and unique identity for each pod.
What's the difference between Kubernetes and Docker Swarm?
Answer: While both are container orchestration tools, Kubernetes is more feature-rich and complex, with a steeper learning curve. Docker Swarm is simpler and more tightly integrated with the Docker ecosystem.
Get matched with Top Kubernetes Experts in minutes 🥳
Hire Top Kubernetes Experts.svg "Braintrust")