Deployment Strategies

Microservices Deployment Strategies

# 1. Rolling Update (K8s default)
kubectl set image deployment/svc svc=myrepo/svc:v2
kubectl rollout undo deployment/svc  # rollback

# 2. Blue-Green
# Run v1 (blue) and v2 (green) simultaneously
# Switch load balancer to green instantly
# Instant rollback: switch back to blue

# 3. Canary (Istio VirtualService)
route:
  - destination: {host: svc, subset: v1}
    weight: 90   # 90% stable
  - destination: {host: svc, subset: v2}
    weight: 10   # 10% canary

# 4. Feature flags (decouple deploy from release)
if feature_flags.is_enabled('new-checkout', user_id):
    return new_checkout()
return old_checkout()