🛠️ Kubernetes Intermediate: Configuration and Management

Kubernetes Intermediate: Configuration and Resource Management

Welcome to part 2 of our Kubernetes tutorial series! In this post, we’ll explore more advanced concepts and learn how to properly configure and manage your applications in Kubernetes.

What We’ll Cover

1. Configuration Management with ConfigMaps
2. Managing Secrets
3. Resource Management
4. Advanced Deployment Strategies

Prerequisites

• Completed our Kubernetes Basics tutorial
• Running Kind cluster
• Basic YAML understanding

ConfigMaps: Managing Application Configuration

ConfigMaps allow you to decouple configuration from your container images.

# config-map.yaml apiVersion: v1 kind: ConfigMap metadata: name: app-config data: app.properties: | environment=development log.level=debug database.properties: | db.url=localhost:5432 db.name=myapp

Using ConfigMaps in Pods

apiVersion: v1 kind: Pod metadata: name: config-test-pod spec: containers: - name: test-container image: busybox volumeMounts: - name: config-volume mountPath: /etc/config volumes: - name: config-volume configMap: name: app-config

Secrets: Managing Sensitive Data

# Create a secret apiVersion: v1 kind: Secret metadata: name: app-secrets type: Opaque data: db-password: BASE64_ENCODED_PASSWORD api-key: BASE64_ENCODED_API_KEY

Using Secrets as Environment Variables

apiVersion: v1 kind: Pod metadata: name: secret-test-pod spec: containers: - name: test-container image: myapp env: - name: DB_PASSWORD valueFrom: secretKeyRef: name: app-secrets key: db-password

Resource Management

Setting Resource Requests and Limits

apiVersion: v1 kind: Pod metadata: name: resource-demo spec: containers: - name: resource-demo-container image: nginx resources: requests: memory: "64Mi" cpu: "250m" limits: memory: "128Mi" cpu: "500m"

Resource Quotas

apiVersion: v1 kind: ResourceQuota metadata: name: compute-quota spec: hard: requests.cpu: "1" requests.memory: 1Gi limits.cpu: "2" limits.memory: 2Gi

Advanced Deployment Strategies

Rolling Updates

apiVersion: apps/v1 kind: Deployment metadata: name: rolling-demo spec: replicas: 3 strategy: type: RollingUpdate rollingUpdate: maxSurge: 1 maxUnavailable: 1 # ... rest of deployment spec

Blue-Green Deployments

# service.yaml apiVersion: v1 kind: Service metadata: name: my-app spec: selector: app: my-app version: blue # Switch between blue and green ports: - port: 80

Hands-on Exercise: Complete Application Setup

Let’s create a complete application setup with:

• ConfigMap for application settings
• Secret for sensitive data
• Deployment with resource limits
• Service for exposure

# Complete example in the repository

What’s Next?

In the next post, we’ll explore:

• StatefulSets and persistent storage
• Networking and Service Mesh
• Monitoring and logging
• Horizontal Pod Autoscaling

Additional Resources

• Kubernetes ConfigMaps and Secrets
• Resource Management
• Deployment Strategies