在初始化期间,Kubernetes MySql映像持久卷非空

Question

我正在处理此处的持久磁盘教程,同时还将其创建为StatefulSet而不是部署.

当我将yaml文件运行到GKE时,数据库无法启动,查看日志时出现以下错误.

[错误] - 指定了初始化但数据目录中包含文件.中止.

是否可以检查创建的卷以查看目录中的内容？否则,我做错了什么导致磁盘非空？

谢谢

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: datalayer-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Gi
---
apiVersion: v1
kind: Service
metadata:
  name: datalayer-svc
  labels:
    app: myapplication
spec:
  ports:
  - port: 80
    name: dbadmin
  clusterIP: None
  selector:
    app: database
---
apiVersion: apps/v1beta2
kind: StatefulSet
metadata:
  name: datalayer
spec:
  selector:
    matchLabels:
      app: myapplication
  serviceName: "datalayer-svc"
  replicas: 1
  template:
    metadata:
      labels:
        app: myapplication
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: database
        image: mysql:5.7.22
        env:
        - name: "MYSQL_ROOT_PASSWORD"
          valueFrom:
            secretKeyRef:
              name: mysql-root-password
              key: password
        - name: "MYSQL_DATABASE"
          value: "appdatabase"
        - name: "MYSQL_USER"
          value: "app_user"
        - name: "MYSQL_PASSWORD"
          value: "app_password"
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: datalayer-pv
          mountPath: /var/lib/mysql
      volumes:
      - name: datalayer-pv
        persistentVolumeClaim:
          claimName: datalayer-pvc

Answer 1

此问题可能是由lost+foundPersistentVolume的文件系统上的目录引起的.

我能够通过添加k8s.gcr.io/busybox容器(在PVC集中accessModes: [ReadWriteMany],或注释掉database容器)来验证这一点:

- name: init
  image: "k8s.gcr.io/busybox"
  command: ["/bin/sh","-c","ls -l /var/lib/mysql"]
  volumeMounts:
  - name: database
    mountPath: "/var/lib/mysql"

有一些潜在的解决方法......

最优选的是subPath在volumeMounts对象上使用a .这使用PersistentVolume的子目录,该子目录在创建时应为空,而不是卷根:

volumeMounts:
- name: database
  mountPath: "/var/lib/mysql"
  subPath: mysql

不太喜欢的解决方法包括:

• 使用一次性容器rm -rf /var/lib/mysql/lost+found(不是一个很好的解决方案,因为该目录由文件系统管理,很可能会重新出现)
• 使用mysql:5image,并添加args: ["--ignore-db-dir=lost+found"]到容器中(此选项已在mysql 8中删除)
• 使用mariadb图像代替mysql

docker-library/mysql问题可能有更多细节:#69和#186