K8S存储之label操作

前面的课程我们学习了如何给pod打标签及修改pod的标签值。在某些特殊情况下，需要将某些服务固定在一台宿主机上, k8s可以使用label给node节点打上标签来满足这种需求。

添加label语法

kubectl label nodes <node-name> <label-key>=<label-value> 

为k8s-node01节点打标签 
kubectl label nodes k8s-node01 mariadb=mariadb 

查看node节点label值 
kubectl get nodes --show-labels

修改Label的值

语法: 需要加上 --overwrite 参数

kubectl label nodes <node-name> <label-key>=<label-value> --overwrite 

修改k8s-node01节点label值 
kubectl label nodes k8s-node01 mariadb=mariadb10.5 --overwrite 

查看node节点label值 
kubectl get nodes --show-labels

删除label语法

注意事项：label的可以后边要增加"-" 
kubectl label nodes <node-name> <label-key>- 

删除k8s-node01节点mariadb的label 
kubectl label nodes k8s-node01 mariadb- 

查看node节点label值 
kubectl get nodes --show-labels

mariaDB部署

通过指定node节点label，将mariaDB部署到指定节点。方便演示volume的各种方式。

指定node

kubectl label nodes k8s-node01 mariadb=mariadb 

查看node节点label值 
kubectl get nodes --show-labels

service部署

在spec.template.spec属性下增加nodeSelector属性。 
spec: 
    nodeSelector: #根据label设置，配置节点选择器 
      mariadb: mariadb #语法规则: key: value 
    containers:

全部资源文件清单

labels/mariadbsecret.yml

apiVersion: v1 
kind: Secret 
metadata: 
  name: mariadbsecret 
type: Opaque 
data: 
  password: YWRtaW4=

labels/mariadb.yml

apiVersion: apps/v1 
kind: Deployment 
metadata: 
  name: mariadb-deploy 
  labels: 
    app: mariadb-deploy 
spec: 
  replicas: 1 
  template: 
    metadata: 
      name: mariadb-deploy 
      labels: 
        app: mariadb-deploy 
    spec: 
      nodeSelector: 
        mariadb: mariadb 
      imagePullSecrets: 
        - name: lagouharbor 
      containers: 
        - name: mariadb-deploy 
          image: 192.168.198.155:5000/lagouedu/mariadb:10.5.2 
          imagePullPolicy: IfNotPresent 
          ports: 
            - containerPort: 3307
          env:
            - name: MYSQL_ROOT_PASSWORD 
            #这是mysqlroot用户的密码 
            valueFrom: 
              secretKeyRef: 
                key: password 
                name: mariadbsecret 
            - name: TZ 
              value: Asia/Shanghai 
          args: 
            - "--character-set-server=utf8mb4" 
            - "--collation-server=utf8mb4_unicode_ci" 
          volumeMounts: 
            - mountPath: /etc/mysql/mariadb.conf.d/ #容器内的挂载目录 
              name: lagoumariadb #随便给一个名字,这个名字必须与volumes.name一致 
      restartPolicy: Always 
      volumes: 
        - name: lagoumariadb 
          configMap: 
            name: mariadbconfigmap 
  selector: 
    matchLabels: 
      app: mariadb-deploy 
--- 
apiVersion: v1 
kind: Service 
metadata: 
  name: mariadb-svc 
spec: 
  selector: 
    app: mariadb-deploy 
  ports: 
    - port: 3307 
      targetPort: 3307 
      nodePort: 30036 
  type: NodePort

labels/mariadbconfigmap.yml

apiVersion: v1 
data: 
  my.cnf: "省略中间数据部分，请各位同学前面章节" 
kind: ConfigMap 
metadata: 
  name: mariadbconfigmap

客户端测试

IP:192.168.198.157 
username:root 
password:admin 
prot: 30036