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Hello Minikube

This tutorial shows you how to run a sample app on Kubernetes using minikube and Katacoda. Katacoda provides a free, in-browser Kubernetes environment.

Note: You can also follow this tutorial if you've installed minikube locally. See minikube start for installation instructions.

Objectives

Deploy a sample application to minikube.
Run the app.
View application logs.

Before you begin

This tutorial provides a container image that uses NGINX to echo back all the requests.

Create a minikube cluster

Click Launch Terminal

Note: If you installed minikube locally, run minikube start. Before you run minikube dashboard, you should open a new terminal, start minikube dashboard there, and then switch back to the main terminal.

Open the Kubernetes dashboard in a browser:
```
minikube dashboard
```
Katacoda environment only: At the top of the terminal pane, click the plus sign, and then click Select port to view on Host 1.
Katacoda environment only: Type 30000, and then click Display Port.

Note:

The dashboard command enables the dashboard add-on and opens the proxy in the default web browser. You can create Kubernetes resources on the dashboard such as Deployment and Service.

If you are running in an environment as root, see Open Dashboard with URL.

By default, the dashboard is only accessible from within the internal Kubernetes virtual network. The dashboard command creates a temporary proxy to make the dashboard accessible from outside the Kubernetes virtual network.

To stop the proxy, run Ctrl+C to exit the process. After the command exits, the dashboard remains running in the Kubernetes cluster. You can run the dashboard command again to create another proxy to access the dashboard.

Open Dashboard with URL

If you don't want to open a web browser, run the dashboard command with the --url flag to emit a URL:

minikube dashboard --url

Create a Deployment

A Kubernetes Pod is a group of one or more Containers, tied together for the purposes of administration and networking. The Pod in this tutorial has only one Container. A Kubernetes Deployment checks on the health of your Pod and restarts the Pod's Container if it terminates. Deployments are the recommended way to manage the creation and scaling of Pods.

Use the kubectl create command to create a Deployment that manages a Pod. The Pod runs a Container based on the provided Docker image.
```
kubectl create deployment hello-node --image=k8s.gcr.io/echoserver:1.4
```

View the Deployment:

kubectl get deployments

The output is similar to:

NAME         READY   UP-TO-DATE   AVAILABLE   AGE
hello-node   1/1     1            1           1m

View the Pod:

kubectl get pods

The output is similar to:

NAME                          READY     STATUS    RESTARTS   AGE
hello-node-5f76cf6ccf-br9b5   1/1       Running   0          1m

View cluster events:
```
kubectl get events
```
View the kubectl configuration:
```
kubectl config view
```

Note: For more information about kubectl commands, see the kubectl overview.

Create a Service

By default, the Pod is only accessible by its internal IP address within the Kubernetes cluster. To make the hello-node Container accessible from outside the Kubernetes virtual network, you have to expose the Pod as a Kubernetes Service.

Expose the Pod to the public internet using the kubectl expose command:
```
kubectl expose deployment hello-node --type=LoadBalancer --port=8080
```
The --type=LoadBalancer flag indicates that you want to expose your Service outside of the cluster.

The application code inside the image k8s.gcr.io/echoserver only listens on TCP port 8080. If you used kubectl expose to expose a different port, clients could not connect to that other port.
View the Service you created:
```
kubectl get services
```
The output is similar to:
```
NAME         TYPE           CLUSTER-IP      EXTERNAL-IP   PORT(S)          AGE
hello-node   LoadBalancer   10.108.144.78   <pending>     8080:30369/TCP   21s
kubernetes   ClusterIP      10.96.0.1       <none>        443/TCP          23m
```
On cloud providers that support load balancers, an external IP address would be provisioned to access the Service. On minikube, the LoadBalancer type makes the Service accessible through the minikube service command.
Run the following command:
```
minikube service hello-node
```
Katacoda environment only: Click the plus sign, and then click Select port to view on Host 1.
Katacoda environment only: Note the 5-digit port number displayed opposite to 8080 in services output. This port number is randomly generated and it can be different for you. Type your number in the port number text box, then click Display Port. Using the example from earlier, you would type 30369.

This opens up a browser window that serves your app and shows the app's response.

Enable addons

The minikube tool includes a set of built-in addons that can be enabled, disabled and opened in the local Kubernetes environment.

List the currently supported addons:

minikube addons list

The output is similar to:

addon-manager: enabled
dashboard: enabled
default-storageclass: enabled
efk: disabled
freshpod: disabled
gvisor: disabled
helm-tiller: disabled
ingress: disabled
ingress-dns: disabled
logviewer: disabled
metrics-server: disabled
nvidia-driver-installer: disabled
nvidia-gpu-device-plugin: disabled
registry: disabled
registry-creds: disabled
storage-provisioner: enabled
storage-provisioner-gluster: disabled

Enable an addon, for example, metrics-server:

minikube addons enable metrics-server

The output is similar to:

The 'metrics-server' addon is enabled

View the Pod and Service you created:

kubectl get pod,svc -n kube-system

The output is similar to:

NAME                                        READY     STATUS    RESTARTS   AGE
pod/coredns-5644d7b6d9-mh9ll                1/1       Running   0          34m
pod/coredns-5644d7b6d9-pqd2t                1/1       Running   0          34m
pod/metrics-server-67fb648c5                1/1       Running   0          26s
pod/etcd-minikube                           1/1       Running   0          34m
pod/influxdb-grafana-b29w8                  2/2       Running   0          26s
pod/kube-addon-manager-minikube             1/1       Running   0          34m
pod/kube-apiserver-minikube                 1/1       Running   0          34m
pod/kube-controller-manager-minikube        1/1       Running   0          34m
pod/kube-proxy-rnlps                        1/1       Running   0          34m
pod/kube-scheduler-minikube                 1/1       Running   0          34m
pod/storage-provisioner                     1/1       Running   0          34m

NAME                           TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)             AGE
service/metrics-server         ClusterIP   10.96.241.45    <none>        80/TCP              26s
service/kube-dns               ClusterIP   10.96.0.10      <none>        53/UDP,53/TCP       34m
service/monitoring-grafana     NodePort    10.99.24.54     <none>        80:30002/TCP        26s
service/monitoring-influxdb    ClusterIP   10.111.169.94   <none>        8083/TCP,8086/TCP   26s

Disable metrics-server:

minikube addons disable metrics-server

The output is similar to:

metrics-server was successfully disabled

Clean up

Now you can clean up the resources you created in your cluster:

kubectl delete service hello-node
kubectl delete deployment hello-node

Optionally, stop the Minikube virtual machine (VM):

minikube stop

Optionally, delete the Minikube VM:

minikube delete

What's next

Learn more about Deployment objects.
Learn more about Deploying applications.
Learn more about Service objects.

© 2022 The Kubernetes Authors
Documentation Distributed under CC BY 4.0.
https://kubernetes.io/docs/tutorials/hello-minikube/