Shounak Khulape

Kubernetes Services - Nodeport

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Shounak Khulape
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Kubernetes Services - Nodeport

Table of contents

NodePort Services in Kubernetes. 🚀

  1. NodePort Service:

    • A NodePort service is the most basic way to get external traffic directly to your service.

    • It opens a specific port on all the Nodes (the VMs) in your Kubernetes cluster.

    • Any traffic sent to this port is forwarded to the associated service

  2. How It Works:

    • When you create a Node Port Service, Kubernetes assigns a port within the range of 30000-32767.

    • End-users can access your application using the node’s IP address and the assigned port

Node Port Services provide a straightforward way to expose your application to the internet. They’re especially useful during development and testing. 🌐🔗

How do I create a Node Port Service in Kubernetes?

NodePort Service in Kubernetes, you have a couple of options:

  1. Using kubectl Command:

    • You can use the kubectl create service nodeport command to create a NodePort service.

    • Here’s an example:

        kubectl create service nodeport my-service --tcp=5678:8080

    • In this example, a new NodePort service named my-service is created, and traffic on port 5678 is forwarded to port 8080 in your Pods

  2. Using kubectl expose Command:

    • Another approach is to use the kubectl expose command with the --type="NodePort" parameter.

    • For instance:

    •   kubectl expose deployment/kubernetes-bootcamp --type="NodePort" --port 8080

How do I expose multiple ports using a Node Port service?

To expose multiple ports using a Node Port Service in Kubernetes, you can define multiple port definitions within the same service. Each port definition can have the same protocol or a different one. Here’s how you can achieve this:

  1. Using YAML Manifest:

    • Create a YAML file (e.g., my-service.yaml) with the following content:

        apiVersion: v1
  kind: Service
  metadata:
    name: my-service
  spec:
    selector:
      app: my-app
    ports:
    - name: http
      port: 80
      targetPort: 8080
    - name: custom-port
      port: 8081
      targetPort: 8081
    type: NodePort

    • In this example, we define two ports: 80 (for HTTP traffic) and 8081 (custom port).

    • Apply the YAML using kubectl apply -f my-service.yaml.

  2. Using kubectl expose Command:

    • Execute the following commands to expose multiple ports:

        kubectl expose deployment my-app --type=NodePort --name=my-service --port=80 --target-port=8080
  kubectl expose service my-service --port=8081 --target-port=8081

    • Replace my-app with your actual deployment name.

Remember to adjust the port numbers (80, 8080, and 8081) and labels (app: my-app) according to your specific use case. This way, your Node Port Service will handle traffic on both ports effectively. 🌐🔗

Kubernetesk8sKubernetes nodeport