Kubernetes Deployment & Liveness/Readiness Probes

1Concept

Kubernetes orchestrates containerized Python microservices. Deployments define replica sets, CPU/RAM resource requests and limits, and configure `livenessProbe` (restarts failed containers) and `readinessProbe` (routes traffic only when the service is ready).

2Architecture Diagram

K8s Ingress ---> K8s Service ---> [ Pod 1: Ready ] [ Pod 2: Ready ] [ Pod 3: Unhealthy -> K8s Restarts! ]

3Code Example

k8s_manifest = '''
apiVersion: apps/v1
kind: Deployment
metadata:
  name: fastapi-microservice
spec:
  replicas: 3
  selector:
    matchLabels:
      app: fastapi-api
  template:
    metadata:
      labels:
        app: fastapi-api
    spec:
      containers:
      - name: api
        image: enterprise-registry.corp/api:v2.1
        ports:
        - containerPort: 8000
        resources:
          requests:
            cpu: "250m"
            memory: "256Mi"
          limits:
            cpu: "1000m"
            memory: "512Mi"
        readinessProbe:
          httpGet:
            path: /health
            port: 8000
          initialDelaySeconds: 5
          periodSeconds: 10
        livenessProbe:
          httpGet:
            path: /health
            port: 8000
          initialDelaySeconds: 15
          periodSeconds: 20
'''
print("=== Production Kubernetes Deployment Manifest ===")
print(k8s_manifest.strip())

4Expected Output

=== Production Kubernetes Deployment Manifest ===
apiVersion: apps/v1
kind: Deployment
metadata:
  name: fastapi-microservice
spec:
  replicas: 3
  selector:
    matchLabels:
      app: fastapi-api
  template:
    metadata:
      labels:
        app: fastapi-api
    spec:
      containers:
      - name: api
        image: enterprise-registry.corp/api:v2.1
        ports:
        - containerPort: 8000
        resources:
          requests:
            cpu: "250m"
            memory: "256Mi"
          limits:
            cpu: "1000m"
            memory: "512Mi"
        readinessProbe:
          httpGet:
            path: /health
            port: 8000
          initialDelaySeconds: 5
          periodSeconds: 10
        livenessProbe:
          httpGet:
            path: /health
            port: 8000
          initialDelaySeconds: 15
          periodSeconds: 20

5Key Takeaways

• ✓Always configure memory limits to prevent out-of-control memory leaks from affecting node neighbors.
• ✓Readiness probes remove pods from service endpoints during warm-up or high load.
• ✓Use Horizontal Pod Autoscaler (HPA) to scale pods based on CPU and request latency metrics.