NGINX Ingress Canary Sends Zero Traffic

You encounter a nginx configuration issue that prevents your workflow from completing. This guide walks through the fix step by step.

Wrong ❌

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-app-canary
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "0" # 0% traffic

Wrong Output

Canary receives zero traffic. Canary weight 0 - no requests forwarded.

Right ✅

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-app-canary
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "10"
    nginx.ingress.kubernetes.io/canary-by-cookie: "canary_user"
spec:
  rules:
    - host: example.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend: { service: { name: my-app-canary, port: { number: 80 } } }

Right Output

Canary receives 10% traffic. Main: 90%. Canary cookie routes specific users.

Prevention

• Set canary-weight between 1-100.
• Use canary-by-cookie or canary-by-header for targeted testing.
• Start with 5-10% and gradually increase.
• Monitor error rates for both versions.
• Remove canary ingress when promoting to full rollout.

DodaTech applies similar defensive patterns across Doda Browser, DodaZIP, and Durga Antivirus Pro infrastructure for production reliability.

Common Mistakes with ingress canary

1. Using head and tail instead of pattern matching, causing runtime errors on empty lists
2. Forgetting that lazy evaluation defers computation until the value is forced, causing space leaks with unevaluated thunks
3. Using return to exit a function early instead of wrapping a pure value in the monad

These mistakes appear frequently in real-world NGINX code. DodaTech's contributors have identified these patterns through analysis of open-source projects and production systems.

Practice Exercise

Write a pure function that safely divides two integers using Maybe, then test it with edge cases like division by zero and negative numbers.

This exercise reinforces the concepts covered in this guide. Try implementing it before checking online solutions.

FAQ

This quick fix is part of the DodaTech infrastructure engineering series. Learn more at DodaTech tutorials.