How to set up RTMP protocol in Ingress Nginx?

Question

I have a Kubernetes cluster set up on Google Kubernetes Engine. I have a pod that hosts an RTMP application. This application requires two ports, one for HTTP and one for RTMP. I have set up an ingress Nginx load balancer. It routes the HTTP traffic correctly. I want to be able to route the RTMP traffic as well. But when I write RTMP in my YAML file. It shows it as an unknown field. I am using skaffold and Google Cloud Build to deploy.

Here is the Ingress-srv file

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress-service
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/use-regex: 'true'
spec:
  rules:
    - http:
        paths:
          - path: /?(.*)
            backend:
              serviceName: stream-server-srv
              servicePort: 8000

What I want to be able to do is have an entry for RTMP on port 1935. That I can then use to stream love videos using RTMP protocol.

Answer 1

RTMP is a TCP-based protocol and standard Ingress does not support TCP services.

The NGINX Ingress controller (which it looks like you are using) can be configured to expose TCP services.

First, you'll need to make sure that you expose both the HTTP and RTMP ports in your stream-server-srv Service:

apiVersion: v1
kind: Service
metadata:
  name: stream-server-srv
  namespace: default
spec:
  selector:
    app: stream-server
  type: ClusterIP
  ports:
    - name: http-port
      port: 8000
      targetPort: 8000
      protocol: TCP
    - name: rtmp-port
      port: 1935
      targetPort: 1935
      protocol: TCP

(replace default with your namespace)

You will also need to make sure that the Service used to expose the NGINX ingress exposes port 1935 as well. For example:

apiVersion: v1
kind: Service
metadata:
  labels:
    app.kubernetes.io/component: controller
    app.kubernetes.io/instance: ingress-nginx
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
    app.kubernetes.io/version: 1.2.0
  name: ingress-nginx-controller
  namespace: ingress-nginx
spec:
  externalTrafficPolicy: Local
  ipFamilies:
  - IPv4
  ipFamilyPolicy: SingleStack
  ports:
  - appProtocol: http
    name: http
    port: 80
    protocol: TCP
    targetPort: http
  - appProtocol: https
    name: https
    port: 443
    protocol: TCP
    targetPort: https
  - name: rtmp
    port: 1935
    protocol: TCP
    targetPort: 1935
  selector:
    app.kubernetes.io/component: controller
    app.kubernetes.io/instance: ingress-nginx
    app.kubernetes.io/name: ingress-nginx
  type: LoadBalancer

Finally, you'll need to update / patch the NGINX tcp services ConfigMap:

kubectl patch configmap tcp-services -n ingress-nginx --patch '{"data":{"1935":"default/stream-server-srv:1935"}}'

(replace "default/stream-server-srv" with your namespace/servicename)