Kubernetes Crash Course

Introduction

• Presented by: Nana
• Purpose: Teach Kubernetes basics in one hour
• Resources: YouTube channel, online courses, DevOps educational program
• Future Learning: Kubernetes Administrator Course and CKA Exam preparation

Course Outline

1. What is Kubernetes?
2. Kubernetes Architecture
3. Key Kubernetes Components
4. Hands-on Demo Project

Understanding Kubernetes

• Definition: Open-source container orchestration framework by Google
• Purpose: Manage applications with hundreds/thousands of containers across different environments
  • Environments: Physical, virtual, cloud, hybrid

Problems Solved by Kubernetes

• High Availability: No downtime, always accessible
• Scalability: Fast scaling (up/down) based on load
• Disaster Recovery: Backup and restore mechanisms for data reliability

Kubernetes Architecture

• Cluster Components:
  • Master Node: API server, controller manager, scheduler, etcd key-value storage
  • Worker Nodes: Hosts containers, runs kubelet process

Master Node Functions

• API Server: Entry point for clients (UI, API, CLI)
• Controller Manager: Oversees cluster health and repairs
• Scheduler: Allocates containers based on resource availability
• etcd Storage: Maintains cluster's current state

Kubernetes Components

• Pods: Abstraction over containers, usually runs a single application
• Services: Static IPs for pods, facilitates communication
  • External Services: For browser access
  • Internal Services: Secure internal communication
• Ingress: Manages external request routing
• Config Maps & Secrets: External configurations and secure data storage
• Volumes: Persistent data storage
• Deployments: Create and manage multiple pod replicas
• Stateful Sets: Manage stateful applications like databases

Setting Up Kubernetes

• MiniKube: Single-node local Kubernetes cluster
• kubectl: CLI tool for interacting with clusters

Installation Steps

1. Install MiniKube using Homebrew
2. Start MiniKube cluster
3. Use kubectl to manage components

Demo Project

• Components: MongoDB and a web application
• Configuration Files:
  • Config Maps: MongoDB URL
  • Secrets: MongoDB username and password
• Deployment:
  • MongoDB and Web App YAML files
  • External service access through NodePort

Key Commands

• kubectl get all: Lists all components
• kubectl describe <resource>: Detailed info about resources
• kubectl logs: Access pod logs

Conclusion

• Advanced Learning: Options to deepen Kubernetes knowledge
• Resources: Kubernetes Administrator Course and DevOps Educational Program
• Call to Action: Links for further learning provided in the video description