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Basic Architecture
minikube - the cluster manager
kubectl - CLI to interact with the cluster manager
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Developing a microservice
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This tutorial shows you how to run a simple Hello World Node.js app on Kubernetes using Minikube and Katacoda. Katacoda provides a free, in-browser Kubernetes environment. You ca find it at https://kubernetes.io/docs/tutorials/hello-minikube/ |
When you start minikube using the command minikube start, it will create a cluster of 1.
Kubernetes Deployment
A Kubernetes Pod is a group of one or more Containers, tied together for the purposes of administration and networking. The Pod in the online 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.
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kubectl create deployment hello-node --image=gcr.io/hello-minikube-zero-install/hello-node |
Use the dashboard to view the changes that have taken place.
- gcr.io is the google container registry, it is similar to hub.docker.com.
- hello-minikube-zero-install/hello-node is the name of the image within the register
- hello-minikube-zero-install/hello-node is the owner of the image within the register
- hello-world after the sub-command deployment is the name of the deployment that will be created
NOTE - if you want to work with the Docker registry see https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/
Creating 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.
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kubectl expose deployment hello-node --type=LoadBalancer --port=8080 |
Run the command minikube service list to get a list of available services. When you do this the hello-world service should have a valid URL you can enter into your browser.
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When you use --expose switch, a Service is created at the same time as you create a Deployment |
Deploying an application into Kubernetes Cluster
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- $Env:POD_NAME=$(kubectl get pods -o go-template --template '{{range .item}}{{.metadata.name}}{{end}}')
- echo $Env:POD_NAME
- curl http://localhost:8001/api/v1/namespaces/default/pods/$Env:POD_NAME/proxy/
Developing a microservice
| Info | ||
|---|---|---|
| ||
This tutorial shows you how to run a simple Hello World Node.js app on Kubernetes using Minikube and Katacoda. Katacoda provides a free, in-browser Kubernetes environment. You ca find it at https://kubernetes.io/docs/tutorials/hello-minikube/ |
When you start minikube using the command minikube start, it will create a cluster of 1.
Kubernetes Deployment
A Kubernetes Pod is a group of one or more Containers, tied together for the purposes of administration and networking. The Pod in the online 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.
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| title | shell command |
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Use the dashboard to view the changes that have taken place.
- gcr.io is the google container registry, it is similar to hub.docker.com.
- hello-minikube-zero-install/hello-node is the name of the image within the register
- hello-minikube-zero-install/hello-node is the owner of the image within the register
- hello-world after the sub-command deployment is the name of the deployment that will be created
NOTE - if you want to work with the Docker registry see https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/
Creating 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.
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kubectl expose deployment hello-node --type=LoadBalancer --port=8080 |
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