☸️ Kubernetes Index
Kubernetes (K8s) is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications.
Overview
Kubernetes provides a framework to run distributed systems resiliently. It handles scaling, failover, deployment patterns, and provides service discovery and load balancing for your applications.
Core Concepts
Fundamentals
- 1 Kubernetes Overview - Introduction to Kubernetes concepts and benefits
- 2 Kubernetes Architecture - Control plane, nodes, and core components
Learning Path
Follow this sequence for optimal understanding:
- Start Here: 1 Kubernetes Overview - Understand what Kubernetes is and why it’s used
- Architecture: 2 Kubernetes Architecture - Learn how Kubernetes works internally
Key Concepts
Kubernetes Components
Control Plane
- API Server - Frontend for Kubernetes control plane
- etcd - Consistent key-value store for cluster data
- Scheduler - Assigns pods to nodes
- Controller Manager - Runs controller processes
Worker Nodes
- kubelet - Agent that runs on each node
- kube-proxy - Network proxy on each node
- Container Runtime - Software for running containers (Docker, containerd)
Core Objects
Pod
- Smallest deployable unit
- One or more containers
- Shared network and storage
Service
- Stable network endpoint
- Load balances across pods
- Service discovery
Deployment
- Declarative updates for pods
- Rolling updates and rollbacks
- Replica management
ConfigMap & Secret
- Configuration management
- Sensitive data handling
Kubernetes vs ECS
| Feature | Kubernetes | ECS |
|---|---|---|
| Complexity | Higher learning curve | Simpler, AWS-native |
| Portability | Cloud-agnostic | AWS-specific |
| Ecosystem | Large, mature ecosystem | AWS ecosystem |
| Management | More configuration needed | Managed by AWS |
| Use Case | Multi-cloud, complex apps | AWS-focused deployments |
Best Practices
Deployment
- Use declarative configuration (YAML)
- Version control your manifests
- Use namespaces for isolation
- Implement resource requests and limits
- Use liveness and readiness probes
Security
- Enable RBAC (Role-Based Access Control)
- Use network policies for pod communication
- Scan container images for vulnerabilities
- Use secrets for sensitive data
- Implement pod security policies
Scaling
- Use Horizontal Pod Autoscaler (HPA)
- Configure cluster autoscaling
- Set appropriate resource requests/limits
- Use pod disruption budgets
Monitoring
- Deploy monitoring stack (Prometheus, Grafana)
- Collect logs centrally
- Set up alerts for critical metrics
- Monitor cluster health and capacity
Related Topics
Prerequisites
- Docker Fundamentals - Container basics
- Container Orchestration - Orchestration concepts
- VPC - Networking foundation
Container Technologies
- ECS - AWS container orchestration alternative
- Dockerfile - Building container images
- Docker Compose - Local multi-container apps
AWS Integration
Advanced Topics
- System Design - Architecture patterns
- AWS Services - Complementary AWS services
Common Use Cases
- Microservices Architecture - Deploy and manage microservices
- Multi-Cloud Deployments - Run workloads across cloud providers
- Hybrid Cloud - Bridge on-premises and cloud infrastructure
- CI/CD Pipelines - Automated deployment workflows
- Batch Processing - Run batch jobs with Job objects
- Stateful Applications - Deploy databases with StatefulSets
AWS Kubernetes Options
Amazon EKS (Elastic Kubernetes Service)
- Managed Kubernetes control plane
- Automatic updates and patching
- Integration with AWS services
- High availability across multiple AZs
Self-Managed Kubernetes on EC2
- Full control over cluster
- More operational overhead
- Custom configurations possible
- Cost optimization opportunities
EKS on Fargate
- Serverless Kubernetes pods
- No node management
- Pay per pod
- Simplified operations
Learning Resources
Official Documentation
- Kubernetes.io - Official documentation
- AWS EKS Documentation - AWS-specific guides
Hands-On Practice
- Minikube - Local Kubernetes cluster
- Kind - Kubernetes in Docker
- EKS Workshop - AWS hands-on labs
Certification
- Certified Kubernetes Administrator (CKA)
- Certified Kubernetes Application Developer (CKAD)
- AWS Certified Solutions Architect
Troubleshooting
Common Issues
- Pods not starting - Check image pull, resource limits, and node capacity
- Service not accessible - Verify service type, selectors, and network policies
- Persistent volume issues - Check storage class and PVC bindings
- Node not ready - Investigate kubelet logs and node resources
- DNS resolution failing - Check CoreDNS pods and service