Starting local Kubernetes using kind and Docker
Introduction
Have you spent all the day trying tutorials of Kubernetes? You don’t have to do that thanks to the latest tools.
In this article, I will show the steps to run a cluster in single Docker container using kind.
What is kind?
kind is a tool for running local Kubernetes clusters using Docker container “nodes”.
https://kind.sigs.k8s.io/
There seems no description but it’s clearly coming from “Kubernetes IN Docker”. Its upside is cross-platform friendliness even with Docker for Windows. Of course, downside is poor googlability as you can see.
Installing kind
Because kind is implemented in go
, make sure the latest golang
is installed. According to contributor’s doc, go1.11.5
or greater is preferred.
To install kind, run these commands (it takes a while)
go get -u sigs.k8s.io/kind
kind create cluster
Then confirm “kind” cluster is available.
kind get clusters
Setting up kubectl
Also, install the latest kubernetes-cli
using Homebrew or Chocolatey.
The latest Docker has Kubernetes feature but it may come with older kubectl
.
Check its version by running this command.
kubectl version
Make sure it shows GitVersion: "v1.14.1"
or above.
If you find you are running kubectl
from Docker, try brew link
or reorder path environment variable.
Once kubectl
and kind are ready, open bash console and run these commands.
export KUBECONFIG=”$(kind get kubeconfig-path)”
kubectl cluster-info
If kind is properly set up, some information will be shown.
Now you are ready to proceed. Yay!
Deploying first application
What should we deploy on the cluster? One good choice will be Wordpress because it consists of MySQL and PHP application.
Luckily, there is an official tutorial which is pretty well described. We can try most steps of it using kind cluster which we just created.
https://kubernetes.io/docs/tutorials/stateful-application/mysql-wordpress-persistent-volume/
First of all, download mysql-deployment.yaml
and wordpress-deployment.yaml
from the page.
And create kustomization.yaml
by running two cat
commands.
Once those yaml
files are prepared, layout them as following,
k8s-wp/
kustomization.yaml
mysql-deployment.yaml
wordpress-deployment.yaml
Then apply them to your cluster.
cd k8s-wp
kubectl apply -k ./
You will see outputs like this if the command succeeded.
secret/mysql-pass-7tt4f27774 created
service/wordpress-mysql created
service/wordpress created
deployment.apps/wordpress-mysql created
deployment.apps/wordpress created
persistentvolumeclaim/mysql-pv-claim created
persistentvolumeclaim/wp-pv-claim created
Let’s check cluster’s status by typing these commands:
kubectl get secrets
kubectl get pvc
kubectl get pods
kubectl get services wordpress
Wait until all the pods become Running
status.
Then, run this command to access the service.
kubectl port-forward svc/wordpress 8080:80
And open http://localhost:8080/
Voila!
If you want to inspect database, check your pods, run a command like this and open your client app.
kubectl port-forward wordpress-mysql-bc9864c58-ffh4c 3306:3306
Conclusion
kind is a good alternative to minikube because it only uses single container of Docker.
By combining Kustomze which was integrated to Kubernetes 1.14, it is pretty straightforward to try it on your local machine.