Need help with custom error sites

Traefik Traefik v1
1

Hello,

I'd like to define custom error-pages with traefik ingress in kubernetes. Although the kubernets-services get 400 or 503 back when I curl them with their ClusterIP, the traefik-ingress does not send my error page, which actually is just a default nginx site.

My config:

apiVersion: v1
items:
- apiVersion: extensions/v1beta1
  kind: Ingress
  metadata:
    annotations:
      certmanager.k8s.io/cluster-issuer: letsencrypt-prod
      ingress.kubernetes.io/ssl-redirect: "true"
      kubernetes.io/ingress.class: traefik-internal
      kubernetes.io/tls-acme: "true"
      traefik.ingress.kubernetes.io/preserve-host: "false"
      traefik.frontend.passHostHeader: "false"
      traefik.ingress.kubernetes.io/error-pages: |-
        foo:
          status:
          - "400"
          - "503"
          backend: all-errors
          query: /
    labels:
      app.kubernetes.io/instance: nextcloud-staging
      app.kubernetes.io/name: nextcloud
    namespace: nextcloud-staging
  spec:
    rules:
    - host: all-errors
      http:
        paths:
        - backend:
            serviceName: nginx
            servicePort: 80
          path: /
    - host: nextcloud.example.org
      http:
        paths:
        - backend:
            serviceName: app-service
            servicePort: 80
          path: /
    tls:
    - hosts:
      - nextcloud.example.org
      secretName: nextcloud.example.org-certificate

Just to see that my error-site works correctly:

# kubectl -n nextcloud-staging get svc nginx
NAME    TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
nginx   NodePort   10.97.208.190   <none>        80:30086/TCP   63m
# curl 10.97.208.190
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
    body {
        width: 35em;
        margin: 0 auto;
        font-family: Tahoma, Verdana, Arial, sans-serif;
    }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

Actually, my nextcloud-app has problem, so the error-code is 400:

# kubectl -n nextcloud-staging get svc app-service 
NAME          TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)   AGE
app-service   ClusterIP   10.99.178.76   <none>        80/TCP    24m
# curl -Sf 10.99.178.76 
curl: (22) The requested URL returned error: 400 Bad Request

But the ingress does not switch to the custom error site:

# curl -fS https://nextcloud.example.org
curl: (22) The requested URL returned error: 400 Bad Request

When I stop my app (with scaling to replica=0), the service is not available anymore, of course:

# kubectl -n nextcloud-staging get svc app-service 
NAME          TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)   AGE
app-service   ClusterIP   10.99.178.76   <none>        80/TCP    26m
# curl -Sf 10.99.178.76 
curl: (7) Failed to connect to 10.99.178.76 port 80: Connection refused

But the ingress does not switch to the error site again:

# curl -fS https://nextcloud.example.org
curl: (22) The requested URL returned error: 503 Service Unavailable

I am looking forward to your help.

Thanks in advance!