Production-Ready Kubernetes Patterns and Best Practices

Introduction

Running Kubernetes in production requires careful consideration of reliability, security, and operational excellence. This guide covers essential patterns and best practices for production-ready Kubernetes deployments.

Deployment Strategies

Rolling Updates with Health Checks

apiVersion: apps/v1
kind: Deployment
metadata:
  name: api-service
  namespace: production
spec:
  replicas: 5
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 1
  selector:
    matchLabels:
      app: api-service
  template:
    metadata:
      labels:
        app: api-service
        version: v2.0.0
    spec:
      containers:
      - name: api
        image: myapp/api:2.0.0
        ports:
        - containerPort: 8080
          name: http
        env:
        - name: DATABASE_URL
          valueFrom:
            secretKeyRef:
              name: db-secret
              key: connection-string
        resources:
          requests:
            memory: "256Mi"
            cpu: "250m"
          limits:
            memory: "512Mi"
            cpu: "500m"
        livenessProbe:
          httpGet:
            path: /health/live
            port: http
          initialDelaySeconds: 30
          periodSeconds: 10
          timeoutSeconds: 5
          failureThreshold: 3
        readinessProbe:
          httpGet:
            path: /health/ready
            port: http
          initialDelaySeconds: 10
          periodSeconds: 5
          timeoutSeconds: 3
          failureThreshold: 3
        startupProbe:
          httpGet:
            path: /health/startup
            port: http
          initialDelaySeconds: 0
          periodSeconds: 10
          timeoutSeconds: 3
          failureThreshold: 30

Blue-Green Deployment

# Blue Deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: app-blue
  labels:
    version: blue
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
      version: blue
  template:
    metadata:
      labels:
        app: myapp
        version: blue
    spec:
      containers:
      - name: app
        image: myapp:1.0.0
        ports:
        - containerPort: 8080

---
# Green Deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: app-green
  labels:
    version: green
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
      version: green
  template:
    metadata:
      labels:
        app: myapp
        version: green
    spec:
      containers:
      - name: app
        image: myapp:2.0.0
        ports:
        - containerPort: 8080

---
# Service that can switch between blue and green
apiVersion: v1
kind: Service
metadata:
  name: myapp-service
spec:
  selector:
    app: myapp
    version: blue  # Switch to 'green' for deployment
  ports:
  - port: 80
    targetPort: 8080

Resource Management

Resource Quotas and Limits

apiVersion: v1
kind: ResourceQuota
metadata:
  name: production-quota
  namespace: production
spec:
  hard:
    requests.cpu: "100"
    requests.memory: 200Gi
    limits.cpu: "200"
    limits.memory: 400Gi
    persistentvolumeclaims: "10"
    services.loadbalancers: "5"
    services.nodeports: "0"

---
apiVersion: v1
kind: LimitRange
metadata:
  name: production-limits
  namespace: production
spec:
  limits:
  - max:
      cpu: "2"
      memory: 4Gi
    min:
      cpu: 100m
      memory: 128Mi
    default:
      cpu: 500m
      memory: 512Mi
    defaultRequest:
      cpu: 250m
      memory: 256Mi
    type: Container
  - max:
      cpu: "8"
      memory: 16Gi
    min:
      cpu: 250m
      memory: 256Mi
    type: Pod

Horizontal Pod Autoscaling

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: api-hpa
  namespace: production
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: api-service
  minReplicas: 3
  maxReplicas: 20
  metrics:
  - type: Resource
    resource:
      name: cpu
      target:
        type: Utilization
        averageUtilization: 70
  - type: Resource
    resource:
      name: memory
      target:
        type: Utilization
        averageUtilization: 80
  - type: Pods
    pods:
      metric:
        name: http_requests_per_second
      target:
        type: AverageValue
        averageValue: "1000"
  behavior:
    scaleDown:
      stabilizationWindowSeconds: 300
      policies:
      - type: Percent
        value: 10
        periodSeconds: 60
      - type: Pods
        value: 2
        periodSeconds: 60
      selectPolicy: Min
    scaleUp:
      stabilizationWindowSeconds: 0
      policies:
      - type: Percent
        value: 100
        periodSeconds: 30
      - type: Pods
        value: 4
        periodSeconds: 30
      selectPolicy: Max

Vertical Pod Autoscaling

apiVersion: autoscaling.k8s.io/v1
kind: VerticalPodAutoscaler
metadata:
  name: api-vpa
  namespace: production
spec:
  targetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: api-service
  updatePolicy:
    updateMode: "Auto"
  resourcePolicy:
    containerPolicies:
    - containerName: api
      minAllowed:
        cpu: 100m
        memory: 128Mi
      maxAllowed:
        cpu: 2
        memory: 2Gi
      controlledResources: ["cpu"
  - memory

Security Best Practices

Pod Security Standards

apiVersion: v1
kind: Namespace
metadata:
  name: production
  labels:
    pod-security.kubernetes.io/enforce: restricted
    pod-security.kubernetes.io/audit: restricted
    pod-security.kubernetes.io/warn: restricted

---
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
  name: restricted
spec:
  privileged: false
  allowPrivilegeEscalation: false
  requiredDropCapabilities:
    - ALL
  volumes:
    - 'configMap'
    - 'emptyDir'
    - 'projected'
    - 'secret'
    - 'downwardAPI'
    - 'persistentVolumeClaim'
  hostNetwork: false
  hostIPC: false
  hostPID: false
  runAsUser:
    rule: 'MustRunAsNonRoot'
  seLinux:
    rule: 'RunAsAny'
  fsGroup:
    rule: 'RunAsAny'
  readOnlyRootFilesystem: true

Network Policies

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: api-network-policy
  namespace: production
spec:
  podSelector:
    matchLabels:
      app: api-service
  policyTypes:
  - Ingress
  - Egress
  ingress:
  - from:
    - namespaceSelector:
        matchLabels:
          name: production
    - podSelector:
        matchLabels:
          app: frontend
    ports:
    - protocol: TCP
      port: 8080
  egress:
  - to:
    - namespaceSelector:
        matchLabels:
          name: production
    - podSelector:
        matchLabels:
          app: database
    ports:
    - protocol: TCP
      port: 5432
  - to:
    - namespaceSelector: {}
    ports:
    - protocol: TCP
      port: 53
    - protocol: UDP
      port: 53

RBAC Configuration

apiVersion: v1
kind: ServiceAccount
metadata:
  name: app-service-account
  namespace: production

---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: app-role
  namespace: production
rules:
- apiGroups: ["
  resources: ["configmaps"
  - secrets
  verbs: ["get"
  - list"
  - watch
- apiGroups: ["
  resources: ["pods
  verbs: ["get"
  - list

---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: app-rolebinding
  namespace: production
subjects:
- kind: ServiceAccount
  name: app-service-account
  namespace: production
roleRef:
  kind: Role
  name: app-role
  apiGroup: rbac.authorization.k8s.io

Observability

Prometheus Monitoring

apiVersion: v1
kind: Service
metadata:
  name: api-service
  labels:
    app: api-service
  annotations:
    prometheus.io/scrape: "true"
    prometheus.io/port: "9090"
    prometheus.io/path: "/metrics"
spec:
  selector:
    app: api-service
  ports:
  - name: http
    port: 80
    targetPort: 8080
  - name: metrics
    port: 9090
    targetPort: 9090

---
apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
metadata:
  name: api-service-monitor
  namespace: production
spec:
  selector:
    matchLabels:
      app: api-service
  endpoints:
  - port: metrics
    interval: 30s
    path: /metrics

Distributed Tracing with OpenTelemetry

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: otel-collector
  namespace: observability
spec:
  selector:
    matchLabels:
      app: otel-collector
  template:
    metadata:
      labels:
        app: otel-collector
    spec:
      serviceAccountName: otel-collector
      containers:
      - name: otel-collector
        image: otel/opentelemetry-collector-contrib:latest
        args: ["--config=/etc/otel-collector-config.yaml
        volumeMounts:
        - name: otel-collector-config
          mountPath: /etc/otel-collector-config.yaml
          subPath: otel-collector-config.yaml
        ports:
        - containerPort: 4317  # OTLP gRPC
        - containerPort: 4318  # OTLP HTTP
        - containerPort: 8888  # Prometheus metrics
        env:
        - name: NODE_NAME
          valueFrom:
            fieldRef:
              fieldPath: spec.nodeName
      volumes:
      - name: otel-collector-config
        configMap:
          name: otel-collector-config

High Availability

Pod Disruption Budgets

apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: api-pdb
  namespace: production
spec:
  minAvailable: 2
  selector:
    matchLabels:
      app: api-service
  unhealthyPodEvictionPolicy: IfHealthyBudget

Pod Anti-Affinity

apiVersion: apps/v1
kind: Deployment
metadata:
  name: api-service
spec:
  replicas: 3
  template:
    spec:
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
              - key: app
                operator: In
                values:
                - api-service
            topologyKey: kubernetes.io/hostname
        podAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 100
            podAffinityTerm:
              labelSelector:
                matchExpressions:
                - key: app
                  operator: In
                  values:
                  - cache
              topologyKey: kubernetes.io/hostname
      topologySpreadConstraints:
      - maxSkew: 1
        topologyKey: topology.kubernetes.io/zone
        whenUnsatisfiable: DoNotSchedule
        labelSelector:
          matchLabels:
            app: api-service

Storage Patterns

StatefulSet with Persistent Volumes

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: postgres
  namespace: production
spec:
  serviceName: postgres-headless
  replicas: 3
  selector:
    matchLabels:
      app: postgres
  template:
    metadata:
      labels:
        app: postgres
    spec:
      containers:
      - name: postgres
        image: postgres:15
        ports:
        - containerPort: 5432
          name: postgres
        env:
        - name: POSTGRES_PASSWORD
          valueFrom:
            secretKeyRef:
              name: postgres-secret
              key: password
        - name: POSTGRES_REPLICATION_MODE
          value: master
        - name: POSTGRES_REPLICATION_USER
          value: replicator
        volumeMounts:
        - name: postgres-storage
          mountPath: /var/lib/postgresql/data
        - name: postgres-config
          mountPath: /etc/postgresql/postgresql.conf
          subPath: postgresql.conf
      volumes:
      - name: postgres-config
        configMap:
          name: postgres-config
  volumeClaimTemplates:
  - metadata:
      name: postgres-storage
    spec:
      accessModes: ["ReadWriteOnce
      storageClassName: fast-ssd
      resources:
        requests:
          storage: 100Gi

Service Mesh Integration

Istio Configuration

apiVersion: networking.istio.io/v1beta1
kind: VirtualService
metadata:
  name: api-service
  namespace: production
spec:
  hosts:
  - api.example.com
  gateways:
  - api-gateway
  http:
  - match:
    - headers:
        x-version:
          exact: v2
    route:
    - destination:
        host: api-service
        subset: v2
      weight: 100
  - route:
    - destination:
        host: api-service
        subset: v1
      weight: 90
    - destination:
        host: api-service
        subset: v2
      weight: 10

---
apiVersion: networking.istio.io/v1beta1
kind: DestinationRule
metadata:
  name: api-service
  namespace: production
spec:
  host: api-service
  trafficPolicy:
    connectionPool:
      tcp:
        maxConnections: 100
      http:
        http1MaxPendingRequests: 100
        http2MaxRequests: 100
        maxRequestsPerConnection: 2
    loadBalancer:
      simple: LEAST_REQUEST
    outlierDetection:
      consecutiveErrors: 5
      interval: 30s
      baseEjectionTime: 30s
      maxEjectionPercent: 50
      minHealthPercent: 30
  subsets:
  - name: v1
    labels:
      version: v1
  - name: v2
    labels:
      version: v2

GitOps with ArgoCD

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: production-app
  namespace: argocd
spec:
  project: default
  source:
    repoURL: https://github.com/myorg/k8s-manifests
    targetRevision: HEAD
    path: production
  destination:
    server: https://kubernetes.default.svc
    namespace: production
  syncPolicy:
    automated:
      prune: true
      selfHeal: true
      allowEmpty: false
    syncOptions:
    - CreateNamespace=true
    - PruneLast=true
    retry:
      limit: 5
      backoff:
        duration: 5s
        factor: 2
        maxDuration: 3m

Conclusion

Building production-ready Kubernetes deployments requires careful attention to reliability, security, performance, and operational excellence. These patterns provide a foundation for running robust, scalable applications in Kubernetes while maintaining high availability and security standards.

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