如何在Kubernetes上创建时初始化mysql容器？

Question

我想在容器的MySQL上设置初始数据。 在docker-compose.yml中，这样的代码可以在运行容器时创建初始数据。

#RevWrapper {
	clear: both;
	margin: auto;
	max-width: 1232px;
	display: block;
	padding-left: calc((100% - 1232px)/2);
	padding-right: calc((100% - 1232px)/2);
	background-color: #006666;
	padding-bottom: 2%;
}
#rev1 {
	clear: both;
	float: left;
	width: 33.3%;
	display: block;
	padding-bottom: 2%;
	padding-top: 2%;
}
#rev2 {
	clear: none;
	float: left;
	width: 33.3%;
	display: block;
	padding-bottom: 2%;
	padding-top: 2%;
}
#rev3 {
	clear: none;
	float: left;
	width: 33.3%;
	display: block;
	padding-bottom: 2%;
	padding-top: 2%;
}
.revimagecenter {    
    display: block;
	width: 85%;
    margin-left: auto;
    margin-right: auto
}

但是，如何在运行时在Kubernetes上创建初始数据？

Answer 1

根据MySQL Docker镜像README，与容器启动时数据初始化相关的部分是确保所有初始化文件都挂载到容器的/docker-entrypoint-initdb.d文件夹中。

您可以在ConfigMap中定义初始数据，并将相应的卷装入您的广告连播中，如下所示：

apiVersion: extensions/v1beta1
kind: Pod
metadata:
  name: mysql
spec:
  containers:
  - name: mysql
    image: mysql        
    ports:
      - containerPort: 3306
    volumeMounts:
      - name: mysql-initdb
        mountPath: /docker-entrypoint-initdb.d
  volumes:
    - name: mysql-initdb
      configMap:
        name: mysql-initdb-config
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: mysql-initdb-config
data:
  initdb.sql: |
    CREATE TABLE friends (id INT, name VARCHAR(256), age INT, gender VARCHAR(3));
    INSERT INTO friends VALUES (1, 'John Smith', 32, 'm');
    INSERT INTO friends VALUES (2, 'Lilian Worksmith', 29, 'f');
    INSERT INTO friends VALUES (3, 'Michael Rupert', 27, 'm');

Answer 2

你需要像这样创建pv和pvclaim然后部署mysql数据库

kind: PersistentVolume
apiVersion: v1
metadata:
  name: sfg-dev-mysql-pv-volume
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/tmp/data"
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: sfg-dev-mysql-pv-claim
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi

创建秘密：

kubectl create secret generic mysql-secret --from-literal=mysql-root-password=kube1234 --from-literal=mysql-user=testadm --from-literal=mysql-password=kube1234
kubectl create configmap db --from-literal=mysql-database: database

mysql部署：

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: sfg-dev-mysql-db
  labels:
    app: sfg-dev-mysql
spec:
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: sfg-dev-mysql
        tier: db
    spec:
      containers:
      - image: mysql:8.0.2
        name: mysql
        env:
        - name: MYSQL_DATABASE
          valueFrom:
            configMapKeyRef:
              name: db
              key: mysql-database        
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-secret
              key: mysql-root-password
        - name: MYSQL_USER
          valueFrom:
            secretKeyRef:
              name: mysql-secret
              key: mysql-user
        - name: MYSQL_PASSWORD
          valueFrom:
            secretKeyRef:
              name: mysql-secret
              key: mysql-password
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: mysql-persistent-storage
          mountPath: /var/lib/mysql
      volumes:
      - name: mysql-persistent-storage
        persistentVolumeClaim:
          claimName: sfg-dev-mysql-pv-claim

Answer 3

首先：创建包含SQL脚本的持久卷

kind: PersistentVolume
apiVersion: v1
metadata:
  name: mysql-initdb-pv-volume
  labels:
    type: local
    app: mysql
spec:
  storageClassName: manual
  capacity:
    storage: 1Mi
  accessModes:
    - ReadOnlyMany
  hostPath:
    path: "/path/to/initdb/sql/scripts"
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: mysql-initdb-pv-claim
  labels:
    app: mysql
spec:
  storageClassName: manual
  accessModes:
    - ReadOnlyMany
  resources:
    requests:
      storage: 1Mi

注意：假设您在/path/to/initdb/sql/scripts中有SQL脚本

第二：将卷安装到/docker-entrypoint-initdb.d

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: mysql
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: mysql
    spec:
      containers:
        - name: mysql
          image: mysql
          imagePullPolicy: "IfNotPresent"
          ports:
            - containerPort: 3306
          volumeMounts:
            - mountPath: /docker-entrypoint-initdb.d
              name: mysql-initdb
      volumes:
        - name: mysql-initdb
          persistentVolumeClaim:
            claimName: mysql-initdb-pv-claim

就是这样。

注意：这也适用于PostgreSQL。