Skip to content

Latest commit

 

History

History
163 lines (77 loc) · 5.62 KB

cm3cxghuu001009jt0kjvgizn.md

File metadata and controls

163 lines (77 loc) · 5.62 KB
Raw
title datePublished cuid slug cover tags
Day 37 Kubernetes Important Interview Questions
Mon Nov 11 2024 11:15:48 GMT+0000 (Coordinated Universal Time)
cm3cxghuu001009jt0kjvgizn
day-37-kubernetes-important-interview-questions
devops, k8s, 90daysofdevops, trainwithshubham, kubernetes-interview-questions, tws

Are you preparing for a Kubernetes interview or just looking to deepen your understanding? This guide covers some essential Kubernetes questions you may encounter. Let’s dive into the key concepts!

1. What is Kubernetes, and Why is It Important?

  • Kubernetes, often referred to as K8s, is an open-source platform for automating the deployment, scaling, and management of containerized applications.

  • It’s crucial because it simplifies operational tasks for distributed systems, improves scalability, and enhances app availability.

2. What is the Difference Between Docker Swarm and Kubernetes?

  • Docker Swarm: Native clustering tool for Docker, simpler but with fewer features.

  • Kubernetes: More complex, robust, and feature-rich, with advanced options for scaling, auto-recovery, and load balancing.

3. How Does Kubernetes Handle Network Communication Between Containers?

  • Kubernetes uses a flat network model, where each pod has a unique IP address, allowing pods to communicate freely within a cluster.

  • Network plugins, like Calico or Flannel, enhance network functionality based on the cluster's needs.

4. How Does Kubernetes Handle Scaling of Applications?

  • Kubernetes automatically scales applications up or down based on metrics like CPU and memory usage.

  • This is achieved through Horizontal Pod Autoscaling (HPA) and Vertical Pod Autoscaling (VPA).

5. What is a Kubernetes Deployment, and How Does It Differ from a ReplicaSet?

  • Deployment: Manages ReplicaSets, supports rolling updates, rollbacks, and maintains a desired state.

  • ReplicaSet: Ensures a specific number of pod replicas are running but lacks update and rollback capabilities.

6. Can You Explain the Concept of Rolling Updates in Kubernetes?

  • Rolling updates in Kubernetes allow you to update your application gradually, without downtime.

  • Kubernetes replaces old versions of pods with new versions incrementally to ensure continuous availability.

7. How Does Kubernetes Handle Network Security and Access Control?

  • Kubernetes uses Network Policies to control the communication between pods.

  • Access control is managed by RBAC (Role-Based Access Control), which restricts user actions within the cluster.

8. Can You Give an Example of Deploying a Highly Available Application in Kubernetes?

  • Deploy multiple replicas across multiple nodes to ensure redundancy.

  • Use Deployments and ReplicaSets to manage pods, and configure Load Balancers to distribute traffic.

9. What is a Namespace in Kubernetes? Which Namespace Does a Pod Use if None is Specified?

  • Namespace: Logical partitioning in a Kubernetes cluster, enabling isolated environments.

  • By default, if no namespace is specified, the pod takes the default namespace.

10. How Does Ingress Help in Kubernetes?

  • Ingress exposes HTTP and HTTPS routes to services within a cluster.

  • It provides a single entry point to route external traffic to the right services, often with load balancing and SSL termination.

11. Different Types of Services in Kubernetes

  • ClusterIP: Exposes the service within the cluster only.

  • NodePort: Exposes the service on each node’s IP at a static port.

  • LoadBalancer: Exposes the service externally with a load balancer.

  • ExternalName: Maps the service to an external DNS name.

12. Can You Explain Self-Healing in Kubernetes and Provide Examples?

  • Kubernetes automatically monitors and replaces failed containers, ensuring application health.

  • Examples include restarting crashed pods, rescheduling pods on healthy nodes, and replacing unresponsive nodes.

13. How Does Kubernetes Handle Storage Management for Containers?

  • Kubernetes supports dynamic and persistent storage management.

  • Persistent Volumes (PV) and Persistent Volume Claims (PVC) are used for long-term storage across containers and sessions.

14. How Does the NodePort Service Work?

  • The NodePort service exposes a pod on a static port on each node, allowing external access to the application using the node’s IP address and NodePort.

15. What is a Multinode Cluster and a Single-Node Cluster in Kubernetes?

  • Single-Node Cluster: All components (control plane and worker nodes) run on one machine, suitable for testing.

  • Multinode Cluster: Multiple nodes for workload distribution, enhancing reliability and scalability.

16. Difference Between kubectl create and kubectl apply

  • kubectl create: Creates resources but will fail if they already exist.

  • kubectl apply: Creates or updates resources based on the specified configuration, making it ideal for applying changes.

Wrapping Up

Understanding these key Kubernetes concepts will give you a solid foundation in interviews and practical applications. Kubernetes is powerful, and mastering it can be highly beneficial for your career in DevOps or cloud-native environments. Good luck!