Consul Ingress Gateway Returns 502

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

Wrong ❌

apiVersion: consul.hashicorp.com/v1alpha1
kind: IngressGateway
metadata: { name: my-ingress }
spec:
  listeners:
    - port: 8080, protocol: http
      services: [{ name: my-service }] # Missing hosts

Wrong Output

Ingress gateway accepts but returns 502. Upstream not found.

Right ✅

apiVersion: consul.hashicorp.com/v1alpha1
kind: IngressGateway
metadata: { name: my-ingress }
spec:
  replicas: 2
  serviceType: LoadBalancer
  listeners:
    - port: 8080, protocol: http
      services: [{ name: my-service, hosts: ["*"] }]
---
apiVersion: consul.hashicorp.com/v1alpha1
kind: ServiceDefaults
metadata: { name: my-service }
spec: { protocol: http }

Right Output

Ingress gateway healthy. 200 OK from upstream. LoadBalancer IP assigned.

Prevention

• Always set hosts in ingress gateway services.
• Create ServiceDefaults with protocol set.
• Set replicas to 2+ for HA.
• Use LoadBalancer service type.
• Verify with kubectl get ingressgateway.

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

Common Mistakes with ingress gateway

1. Forgetting deriving (Show, Eq) on custom data types needed for debugging
2. Placing the wildcard pattern first in case expressions, making all subsequent patterns unreachable
3. Using head and tail instead of pattern matching, causing runtime errors on empty lists

These mistakes appear frequently in real-world CONSUL 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.