nginx-ingress config map snippets being ignored by the nginx.conf

Question

I have a kubernetes cluster, where I have deployed an nginx ingress controller using the helm nginx-ingress chart.

I need to add some custom config to the nginx.conf file that is generated in the nginx-controller-pod, and I am seeing an issue where if I add a one line option such as proxy-buffer-size: "512k" I can see this reflected in the nginx.conf file and everything works as expected.

However, if I attempt to add a snippet to accomplish the same thing:

location-snippet: |
  proxy_buffer_size "512k";

It is as though this is ignored by the nginx.conf file and the proxy_buffer_size setting remains at it's default value.

I need to be able to add http-snippet, server-snippet and location-snippet overrides but whether I try to add them to the ConfigMap or as an annotation in the Ingress.yaml file they are always ignored.

My Ingress yaml file:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: my-ingress
  annotations:
    kubernetes.io/ingress.class: nginx
    ingress.kubernetes.io/ssl-redirect: "true" 
    ingress.kubernetes.io/secure-backends: "true"    
    ingress.kubernetes.io/force-ssl-redirect: "true"

    ingress.kubernetes.io/location-snippet: |
       proxy_buffer_size 512k;     --This does not update the nginx.conf
spec:
  tls:
  - hosts:
    - my.app.co.uk
    secretName: tls-secret

  rules:
  - host: my.app.co.uk
    http:
      paths:
      - path: /
        backend:
          serviceName: myappweb-service
          servicePort: 80

My nginx config map:

apiVersion: v1
kind: ConfigMap
metadata:
  labels:
    app: nginx-ingress
    chart: nginx-ingress-0.28.3
    component: controller
    heritage: Tiller
    release: nginx-ingress
  name: nginx-ingress-controller
  namespace: default
data:
  proxy-buffer-size: "512k" -- this works and updates the nginx.conf

  location-snippet: |
    proxy_buffers 4 512k; -- this does not update the nginx.conf

  server-snippet: |       -- this does not update the nginx.conf
    location /messagehub {
      proxy_set_header Upgrade $http_upgrade;
      proxy_http_version 1.1;
      proxy_set_header X-Forwarded-Host $http_host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_set_header X-Forwarded-For $remote_addr;
      proxy_set_header Host $host;
      proxy_set_header Connection "upgrade";
      proxy_cache_bypass $http_upgrade;
   }

Answer 1

If you'd like to modify your Kubernetes Ingress the annotation options are these:

• nginx.ingress.kubernetes.io/configuration-snippet for an nginx location block snippet
• nginx.ingress.kubernetes.io/server-snippet for a snippet in the nginx config service block

Looks like you are using nginx.org/location-snippets: for that case.

There's also a YAML invalid syntax on nginx config example and also you should use plurals as in server-snippets according to this example. There's a typo in the docs as of this writing. Opened this ticket to follow up.

It should be something like this:

  server-snippets: |
    location /messagehub {
      proxy_set_header Upgrade $http_upgrade;
      proxy_http_version 1.1;
      proxy_set_header X-Forwarded-Host $http_host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_set_header X-Forwarded-For $remote_addr;
      proxy_set_header Host $host;
      proxy_set_header Connection "upgrade";
      proxy_cache_bypass $http_upgrade;
      }

instead of this:

  server-snippet: |
    location /messagehub {
      proxy_set_header Upgrade $http_upgrade;
      proxy_http_version 1.1;
      proxy_set_header X-Forwarded-Host $http_host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_set_header X-Forwarded-For $remote_addr;
      proxy_set_header Host $host;
      proxy_set_header Connection "upgrade";
      proxy_cache_bypass $http_upgrade;
    }

Notice the indentation of the last curly brace.

Answer 2

I spent a day untill got that for ingress-nginx (from Kubernetes) there are *-snippet, but for nginx-ingress (from NGINX) that *-snippets with s.

Look here:

• ingress-nginx: https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/configmap/#main-snippet
• nginx-ingress: https://docs.nginx.com/nginx-ingress-controller/configuration/global-configuration/configmap-resource/#snippets-and-custom-templates

Answer 3

If some needs solution for Kubernetes 1.23 and Helm 3, here is my answer in the similar topic.