How to Build Your K8S Service

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How to Build Your K8S Service

Today we will use minikube tool build own K8S Service,Minikube is local Kubernetes, focusing on making it easy to learn and develop for Kubernetes.

All you need is Docker (or similarly compatible) container or a Virtual Machine environment, and Kubernetes is a single command away: 

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minikube start

What you’ll need

1、2 CPUs or more
2、2GB of free memory
3、20GB of free disk space
4、Internet connection
5、Container or virtual machine manager, such as: Docker, QEMU, Hyperkit, Hyper-V, KVM, Parallels, Podman, VirtualBox, or VMware Fusion/Workstation

1、Install MiniKube

Click on the buttons that describe your taget platform. For other architectures, see the minikute release page for a complete list of minikube binaries.

To install the lastes minikube stable release on x86-64 Linux using binary download.

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curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64
sudo install minikube-linux-amd64 /usr/local/bin/minikube

Other platform, you can see it Minikube Install Doc

2、 Minikube Start Your Cluster

From a terminal with administrator access(but not logged in as root) run:

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minikube start

If minikube fails to start,see the drivers page for help setting up a compatible container or virtual-machine manager.

3、Interact with your cluster

If you already have kubectl installed (see document), you can now use it to access your shiny new cluster:

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kubectl get po -A

Alternatively,minikube can download the appropriate verson of kubectl and you should be able to use it like this:

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minikube kubectl --get po -A

You can also make your life easier by adding the follwing to your shelf config:

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alias kubectl="minikube kubectl ---"

Initialy, some services such as the storage-provisioner, may not yet be in a Running state. This is a normal condition during cluster bring-up, and will resolve itself momentarily. For additional insight into your cluster state, minikube bundles the Kubernetes Dashboard, allowing you to get easily acclimated to your new environment:

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minikube dashboard

4、Deploy Applications

4.1 Deploy Service

Create a sample deployment and expose it on port 8080:

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kubectl create deployment hello-minikube --image=kicbase/echo-server:1.0
kubectl expose deployment hello-minikube --type=NodePort --port=8080

It may take a moment, but your deployment will soon show up when you run:

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kubectl get services hello-minikube

The easiest way to access this service is to let minikube launch a web browser for you:

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minikube service hello-minikube

Alternatively, use kubectl to forward the port:

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kubectl port-forward service/hello-minikube 7080:8080

Tada! Your application is now available at http://localhost:7080/.

You should be able to see the request metadata in the application output. Try changing the path of the request and observe the changes. Similarly, you can do a POST request and observe the body show up in the output.

4.2 Deploy LoadBalancer

To access a LoadBalancer deployment, use the “minikube tunnel” command. Here is an example deployment:

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kubectl create deployment balanced --image=kicbase/echo-server:1.0
kubectl expose deployment balanced --type=LoadBalancer --port=8080

In another window, start the tunnel to create a routable IP for the ‘balanced’ deployment:

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minikube tunnel

To find the routable IP, run this command and examine the EXTERNAL-IP column:

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kubectl get services balanced

Your deployment is now available at :8080

4.3 Deploy Ingress

Enable ingress addon:

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minikube addons enable ingress

The following example creates simple echo-server services and an Ingress object to route to these services.

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kind: Pod
apiVersion: v1
metadata:
  name: foo-app
  labels:
    app: foo
spec:
  containers:
    - name: foo-app
      image: 'kicbase/echo-server:1.0'
---
kind: Service
apiVersion: v1
metadata:
  name: foo-service
spec:
  selector:
    app: foo
  ports:
    - port: 8080
---
kind: Pod
apiVersion: v1
metadata:
  name: bar-app
  labels:
    app: bar
spec:
  containers:
    - name: bar-app
      image: 'kicbase/echo-server:1.0'
---
kind: Service
apiVersion: v1
metadata:
  name: bar-service
spec:
  selector:
    app: bar
  ports:
    - port: 8080
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: example-ingress
spec:
  rules:
    - http:
        paths:
          - pathType: Prefix
            path: /foo
            backend:
              service:
                name: foo-service
                port:
                  number: 8080
          - pathType: Prefix
            path: /bar
            backend:
              service:
                name: bar-service
                port:
                  number: 8080
---

Apply the contents

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kubectl apply -f https://storage.googleapis.com/minikube-site-examples/ingress-example.yaml

Wait for ingress address

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kubectl get ingress
NAME              CLASS   HOSTS   ADDRESS          PORTS   AGE
example-ingress   nginx   *       <your_ip_here>   80      5m45s

Note for Docker Desktop Users:
To get ingress to work you’ll need to open a new terminal window and run minikube tunnel and in the following step use 127.0.0.1 in place of .

Now verify that the ingress works

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$ curl <ip_from_above>/foo
Request served by foo-app
...

$ curl <ip_from_above>/bar
Request served by bar-app
...

Referce

MiniKube
Minikube Handbook
Minikube command reference