Migrate from ingress-nginx to Gateway API

[bussyjd]

Migrate from ingress-nginx to Gateway API

Summary

The Kubernetes ingress-nginx project is retiring in March 2026. After that date, there will be no releases, bugfixes, or security updates. We need to migrate to the Gateway API standard.

Source: https://www.kubernetes.dev/blog/2025/11/12/ingress-nginx-retirement/

Current State

We currently use ingress-nginx (v4.13.3) with Traefik explicitly disabled. All applications route through ingress-nginx:

• Obol Frontend: / path
• eRPC: /rpc path
• Helios: /helios path (disabled)
• Ethereum: /ethereum/execution and /ethereum/beacon with URL rewriting

Proposed Solution

Migrate to Gateway API using a simple gateway architecture as described in https://gateway-api.sigs.k8s.io/guides/simple-gateway/

Our use case is straightforward:

• Single host: obol.stack
• Basic HTTP path-based routing
• URL rewriting for ethereum endpoints

Implementation Steps

1. Choose Controller:

   • Option A: NGINX Gateway Fabric (keeps NGINX)
   • Option B: Re-enable k3s built-in Traefik

2. Install Gateway API CRDs

3. Create Single Gateway Resource:

apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: obol-gateway
spec:
  gatewayClassName: nginx  # or traefik
  listeners:
  - name: http
    protocol: HTTP
    port: 80
    hostname: obol.stack

4. Convert Ingress → HTTPRoute (example):

apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: obol-frontend
spec:
  parentRefs:
  - name: obol-gateway
  hostnames:
  - obol.stack
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /
    backendRefs:
    - name: obol-frontend
      port: 3000

5. Handle URL Rewriting with URLRewrite filters for ethereum endpoints

6. Update Documentation

Files to Change

• internal/embed/k3d-config.yaml - Controller configuration
• internal/embed/defaults/helmfile.yaml - Replace ingress-nginx
• internal/embed/defaults/values/*.yaml.gotmpl - Convert to HTTPRoute
• internal/embed/charts/ethereum/templates/ingress.yaml - Convert to HTTPRoute
• CLAUDE.md - Update architecture docs

Timeline

• Hard Deadline: March 2026
• Recommended: ASAP

References

• https://www.kubernetes.dev/blog/2025/11/12/ingress-nginx-retirement/
• https://gateway-api.sigs.k8s.io/guides/simple-gateway/
• https://gateway-api.sigs.k8s.io/