Bits of .NET

❤️ Is Your App Alive AND Ready?

Liveness = restart if dead. Readiness = don’t send traffic until ready. Startup = extra time for slow-starting apps. Use all three for reliability.

📝 Probe Configuration

livenessProbe:
  httpGet:
    path: /healthz
    port: 8080
  initialDelaySeconds: 30
  periodSeconds: 10
  timeoutSeconds: 5
  failureThreshold: 3

readinessProbe:
  httpGet:
    path: /ready
    port: 8080
  initialDelaySeconds: 5
  periodSeconds: 5
  failureThreshold: 3

startupProbe:
  httpGet:
    path: /healthz
    port: 8080
  failureThreshold: 30
  periodSeconds: 10

🎯 Probe Types

// HTTP Probe (most common)
livenessProbe:
  httpGet:
    path: /health
    port: 8080
    httpHeaders:
    - name: Custom-Header
      value: Awesome

// TCP Probe (for databases, Redis)
readinessProbe:
  tcpSocket:
    port: 3306

// Command Probe (exec)
livenessProbe:
  exec:
    command:
    - cat
    - /tmp/healthy

💡 Best Practices

• Liveness: check only essential internal state (no dependencies)
• Readiness: check database, cache, external APIs
• Startup: for apps with long startup time (Java, Node.js large apps)
• Set failureThreshold to 3 (avoid flapping)
• Don’t use same endpoint for liveness and readiness