在自己的电脑上运行k8s可以很方便的测试你得k8s yaml文件，之前有minikube单它并不支持multi-node. 最近kind开始流行起来，而且它与WSL (Windows Substem Linux)集成的很好。那么我们就开始用kind吧.

` Why kind? kind supports multi-node (including HA) clusters kind supports building Kubernetes release builds from source support for make / bash or docker, in addition to pre-published builds kind supports Linux, macOS and Windows kind is a CNCF certified conformant Kubernetes installer `

安装kind并创建你的第一个k8s cluster

一个cluster就是多个nodes的集合，就是一个k8s unit。下面示例中，我们创建了一个名叫wslkind的cluster,并把kubeconfig配置文件写入了 $~/.kube/config文件中

# Check if the KUBECONFIG is not set
echo $KUBECONFIG
# Check if the .kube directory is created > if not, no need to create it
ls $HOME/.kube
# Create the cluster and give it a name (optional)
kind create cluster --name wslkind
# Check if the .kube has been created and populated with files
ls $HOME/.kube
# list clusters that has been created
kind get clusters
# Check how many nodes it created
kubectl get nodes
# Check the services for the whole cluster
kubectl get all --all-namespaces

安装helm并部署你的第一个k8s service

helm可以帮助你部署k8s service, 参考helm主页: https://helm.sh/docs/intro/quickstart/

  1. Create a example service using helm and create namespace if it does not exist 
    helm install bitnami/mysql --generate-name --create-namespace --namespace zhuolins

Tip:

Watch the deployment status using the command: kubectl get pods -w --namespace zhuolins

Services:

  echo Primary: mysql-1622777550.zhuolins.svc.cluster.local:3306

Administrator credentials:

  echo Username: root
  echo Password : $(kubectl get secret --namespace zhuolins mysql-1622777550 -o jsonpath="{.data.mysql-root-password}" | base64 --decode)

To connect to your database:

  1. Run a pod that you can use as a client: 
     kubectl run mysql-1622777550-client --rm --tty -i --restart='Never' --image  docker.io/bitnami/mysql:8.0.25-debian-10-r16 --namespace zhuolins --command -- bash
  2. To connect to primary service (read/write): 
     mysql -h mysql-1622777550.zhuolins.svc.cluster.local -uroot -p my_database

    To upgrade this helm chart:

  3. Obtain the password as described on the ‘Administrator credentials’ section and set the ‘root.password’ parameter as shown below: 
     ROOT_PASSWORD=$(kubectl get secret --namespace zhuolins mysql-1622777550 -o jsonpath="{.data.mysql-root-password}" | base64 --decode)
 helm upgrade --namespace zhuolins mysql-1622777550 bitnami/mysql --set auth.rootPassword=$ROOT_PASSWORD