HOW TO: expose multiple nodeports in Kubernetes(OKE) via single public IP adress

User_LEOWY

Hello,

Is there any solution, how to expose multiple nodeports inside Kubernetes cluster via single public IP address?

Example:

prometheus nodeport: 30001

elastic nodeport: 30002

And all these nodeports will be handle by single public IP address. Then If I need to configure output for some app that needs to reach elastic I will use IP xxx.xxx.xxx.xxx:30002

Same with output for prometheus. The IP will be same xxx.xxx.xxx.xxx only nodeport will be different.

I know I can create LB for each of these but then I will have different IPs.

Is there any way how to do that?

Many thanks in advance.

Martin

Edwin van Meerendonk

Yes, you can create a service, but you can create it for multiple ports.

apiVersion: v1
kind: Service
metadata:
  name: external-shared-lb
  annotations:
    oci.oraclecloud.com/load-balancer-type: "nlb"
spec:
  type: LoadBalancer
  ports:
  - name: nodered-anexo-pv1c
    port: 8080
    targetPort: nodered-port
  - name: influxdb1
    port: 8081
    targetPort: influxdb-port
  selector:
    lbtype: external-shared

Here I create a network loadbalancer that will receive a single IP, but it will listen to port 8080 and 8081.

In you deployment you have to name the target-ports

 spec:
      containers:
      - name: influxdb1
        image: ***
        ports:
        - containerPort: 8086
          name: influxdb-port

So, external traffic on my loadbalancer on 8081 will be directed to the pod(s) on port 8086

Edwin van Meerendonk

Sorry, I forgot the lbtype tag in the selector.

The full deployment example

apiVersion: apps/v1
kind: Deployment
metadata:
  name: influxdb1
spec:
  selector:
    matchLabels:
      app: influxdb1app
  replicas: 1
  template:
    metadata:
      labels:
        app: influxdb1app
        lbtype: external-shared
    spec:
      containers:
      - name: influxdb1
        image: ****
        ports:
        - containerPort: 8086
          name: influxdb-port
      imagePullSecrets:
        - name: classified