50+ Kubernetes Interview Questions That Will Challenge Even the Most Seasoned DevOps Engineers!
Hey there! I’ve put together a list of 50+ Kubernetes interview questions that I’m excited to share with you all.
This is a great opportunity to test your knowledge and see how well you really know Kubernetes.
These questions will challenge you and highlight areas for improvement. I’m eager to see how you all tackle these and look forward to some insightful discussions on comment box!
Here are the list of Kubernetes interview Questions:
Cluster Architecture
- Can you explain the different components of the Kubernetes control plane and their roles?
- How does the etcd datastore work within a Kubernetes cluster, and why is it crucial?
Networking
- How does the Kubernetes networking model work, especially the concepts of Pods, Services, and Ingress?
- Can you explain the difference between ClusterIP, NodePort, and LoadBalancer services?
- Your cluster nodes have two NICs connected to different networks. How do you bootstrap the cluster, and what issues could you face?
- Please explain the journey of a packet from one pod to another.
Pod Lifecycle
- What are the different phases in the lifecycle of a Pod, and what happens during each phase?
- How do you handle Pod scheduling, and what strategies can you use to ensure Pods are efficiently scheduled?
- What happens if a container doesn’t pass the ReadinessProbe?
- What is the difference between a Deployment and a StatefulSet?
- What is a Headless Service?
- How can we run Static Pods?
- What is a Pod Sandbox?
Storage
- How does Kubernetes manage persistent storage, and what are the differences between Persistent Volumes (PVs) and Persistent Volume Claims (PVCs)?
- Can you explain the concept of StorageClasses and how they are used in dynamic provisioning?
- What happens if you have a PodDisruptionBudget (PDB) with a max unavailable of 2, and you want to drain a node where a pod of the deployment is in a CrashLoop?
- How do you fix an issue where a Postgres pod crashes due to a configuration error on the PVC?
Security
- How does Kubernetes manage access control, and what are the key components of RBAC (Role-Based Access Control)?
- What are Network Policies, and how do they enhance security within a Kubernetes cluster?
- Which RBAC permissions can lead to Privilege Escalation within the cluster and why?
Configuration Management
- How do ConfigMaps and Secrets differ, and when would you use each?
- What are the best practices for managing environment-specific configurations in a Kubernetes cluster?
- How do you cancel deletion for a resource (e.g., Ingress) which has a finalizer attached to it?
Scaling and Performance
- How do you implement horizontal and vertical scaling in Kubernetes?
- What tools and metrics do you use to monitor and optimize the performance of a Kubernetes cluster?
CI/CD Integration
- How would you integrate Kubernetes with a CI/CD pipeline?
- What are the benefits and challenges of using tools like Helm and Kustomize in a CI/CD process?
- Consider you have a Kubernetes cluster that is integrated with Argo as its CD pipeline. How do you break out of an infinite loop where Argo keeps triggering a Kubernetes Job?
Advanced Topics
- Can you explain the concept of Operators and how they extend Kubernetes functionality?
- What are Custom Resource Definitions (CRDs), and how do they allow for the creation of custom resources within Kubernetes?
- When should you use (or customize) an operator?
- For Helm templates, is there any standard practice on how to group your app e.g by backend/frontend?
Troubleshooting
- How do you debug a failing Pod in a Kubernetes cluster?
- What steps would you take if you notice a node is not joining the cluster?
- How do you troubleshoot a node that suddenly stops resolving DNS queries, and the service management tool in use is systemd?
- How do you bootstrap the cluster, what issues could you run into, and how do you solve them?
- Tell me everything that happens from the point you execute kubectl create -f pod.yaml until the pod is running.
- Where can you look to see if a required mutating webhook is failing?
- How do you handle a scenario where a Postgres pod crashes due to a misconfiguration on the PVC?
Miscellaneous
- What is the difference between a readiness probe, liveness probe, and startup probe, and when would you use each?
- What are endpoints, and how are they related to services?
- Define Kubernetes using an analogy.
- What problem does Kubernetes solve?
- Choose a metrics and logs plugin, and explain how you’re going to export container logs and metrics out of Kubernetes.
- How does kube-proxy load balance services?
- What is a pause container?
- How are DaemonSet Pods scheduled on Nodes?
