Kubernetes

What I do

• Create and manage Kubernetes manifests
• Deploy applications using kubectl and Helm
• Configure services, ingress, and networking
• Set up persistent storage
• Implement config maps and secrets
• Manage deployments with rolling updates
• Configure resource limits and auto-scaling

When to use me

When deploying containerized applications to Kubernetes clusters.

Pod

apiVersion: v1
kind: Pod
metadata:
  name: my-app
  labels:
    app: my-app
spec:
  containers:
  - name: app
    image: my-app:latest
    ports:
    - containerPort: 8080
    resources:
      requests:
        memory: "64Mi"
        cpu: "250m"
      limits:
        memory: "128Mi"
        cpu: "500m"

Deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-app
spec:
  replicas: 3
  selector:
    matchLabels:
      app: my-app
  template:
    metadata:
      labels:
        app: my-app
    spec:
      containers:
      - name: app
        image: my-app:v1
        ports:
        - containerPort: 8080
        env:
        - name: DATABASE_URL
          valueFrom:
            secretKeyRef:
              name: db-credentials
              key: url

Service

apiVersion: v1
kind: Service
metadata:
  name: my-app
spec:
  selector:
    app: my-app
  ports:
  - port: 80
    targetPort: 8080
  type: ClusterIP  # or NodePort, LoadBalancer

Ingress

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-app
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  rules:
  - host: myapp.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: my-app
            port:
              number: 80

ConfigMap & Secrets

apiVersion: v1
kind: ConfigMap
metadata:
  name: app-config
data:
  database.json: |
    {"host": "localhost", "port": 5432}
---
apiVersion: v1
kind: Secret
metadata:
  name: app-secret
type: Opaque
stringData:
  api-key: your-api-key-here

StatefulSet

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: mysql
spec:
  serviceName: mysql
  replicas: 3
  selector:
    matchLabels:
      app: mysql
  template:
    spec:
      containers:
      - name: mysql
        image: mysql:8
        volumeMounts:
        - name: data
          mountPath: /var/lib/mysql
  volumeClaimTemplates:
  - metadata:
      name: data
    spec:
      accessModes: ["ReadWriteOnce"]
      resources:
        requests:
          storage: 10Gi

Helm Chart

# Install
helm install my-release my-chart/

# Upgrade
helm upgrade my-release my-chart/ --set image.tag=v2

# Values
helm install my-release my-chart/ -f values.yaml

# values.yaml
replicaCount: 3

image:
  repository: my-app
  tag: latest
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80

resources:
  limits:
    cpu: 500m
    memory: 256Mi