Bits of .NET

📈 Scale Pods Automatically

Fixed replicas waste resources. HorizontalPodAutoscaler scales pods based on CPU/memory. Scale up during load, down during low traffic.

📝 HPA Configuration

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: myapp-hpa
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: myapp
  minReplicas: 2
  maxReplicas: 10
  metrics:
  - type: Resource
    resource:
      name: cpu
      target:
        type: Utilization
        averageUtilization: 70
  - type: Resource
    resource:
      name: memory
      target:
        type: Utilization
        averageUtilization: 80

🎯 Check HPA Status

# Check HPA
kubectl get hpa

# Describe HPA
kubectl describe hpa myapp-hpa

# Watch HPA
kubectl get hpa -w

# HPA output:
NAME         REFERENCE          TARGETS   MINPODS   MAXPODS   REPLICAS
myapp-hpa    Deployment/myapp   45%/70%   2         10        2

# Simulate load
kubectl run load-generator --image=busybox -- /bin/sh -c "while true; do wget -q -O- http://myapp; done"

# Watch scale up
kubectl get hpa -w

# TARGETS: 45%/70% → 85%/70% → Scaling up!
# REPLICAS: 2 → 4 → 6 → 8

💡 Best Practices

• Set resource requests for accurate scaling
• minReplicas: 2 (availability)
• maxReplicas: 10 (cost control)
• Target utilization: 70% (buffer)
• Monitor metrics for scaling decisions