K8S部署mysql 5.7.39实践

       k8s部署MySQL无外乎要解决两个问题，第一就是数据的持久存储问题，第二配置文件的同步问题。

下面要围绕这两方面的问题进行阐述

一、数据的持久存储问题

（一）PV的yml文件

apiVersion: v1
kind: PersistentVolume
metadata:
  name: mysql-pv
spec:
  capacity:
    storage: 8Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: nfs
  nfs:
    path: /home/nfsdata/mysql-pv
    server: 192.168.10.8

（二）PVC的yml文件

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 8Gi
  storageClassName: nfs

（三）deployment 部署mysql：5.7.39

apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
  labels:
    app: mysql
spec:
  selector:
    matchLabels:
      app: mysql
  template:
    metadata:
      labels:
        app: mysql
    spec:
      containers:
      - name: mysql
        image: mysql:5.7.39
        env:
           - name: MYSQL_ROOT_PASSWORD
             value: 123456
        ports:
           - containerPort: 3306
             name: mysql
        volumeMounts: # 挂载Pod上的卷到容器
           - name: mysql-persistent-storage # Pod上卷的名字，与“volumes”名字匹配
             mountPath: /var/lib/mysql # 挂载的Pod的目录
      volumes:   # 挂载持久卷到Pod
        - name: mysql-persistent-storage # 持久卷名字， 与“volumMounts”名字匹配
          persistentVolumeClaim:
            claimName: mysql-pvc  # 持久卷申请名字

（四）service的部署

apiVersion: v1
kind: Service
metadata:
  name: mysql
spec:
  type: NodePort
  ports:
     - protocol: TCP
       nodePort: 30306
       port: 3306
       targetPort: 3306
  selector:
       app: mysql

二、配置文件的同步问题

（一）configmap的定义

apiVersion: v1
kind: ConfigMap
metadata:
  name: mysql-configmap
data:
  # 类文件键
  my.cnf: |
       [mysqld]
       # Remove leading # and set to the amount of RAM for the most important data
       # cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
       # innodb_buffer_pool_size = 128M
       #
       # Remove leading # to turn on a very important data integrity option: logging
       # changes to the binary log between backups.
       # log_bin
       #
       # Remove leading # to set options mainly useful for reporting servers.
       # The server defaults are faster for transactions and fast SELECTs.
       # Adjust sizes as needed, experiment to find the optimal values.
       # join_buffer_size = 128M
       # sort_buffer_size = 2M
       # read_rnd_buffer_size = 2M
         skip-host-cache
         skip-name-resolve
         datadir=/var/lib/mysql
         socket=/var/run/mysqld/mysqld.sock
         secure-file-priv=/var/lib/mysql-files
         user=mysql

         lower_case_table_names=1
         event_scheduler=ON
         max_connections=2000
         wait_timeout=1800
         max_user_connections=800
         sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION'

       # Disabling symbolic-links is recommended to prevent assorted security risks
         symbolic-links=0

       #log-error=/var/log/mysqld.log
        pid-file=/var/run/mysqld/mysqld.pid

         [client]
         socket=/var/run/mysqld/mysqld.sock

        !includedir /etc/mysql/conf.d/
        !includedir /etc/mysql/mysql.conf.d/

（二）重新进行挂载configmap

apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
  labels:
    app: mysql
spec:
  selector:
    matchLabels:
      app: mysql
  template:
    metadata:
      labels:
        app: mysql
    spec:
      containers:
      - name: mysql
        image: mysql:5.7.39
        env:
           - name: MYSQL_ROOT_PASSWORD
             value: 123456
        ports:
           - containerPort: 3306
             name: mysql
        volumeMounts: # 挂载Pod上的卷到容器
           - name: mysql-persistent-storage # Pod上卷的名字，与“volumes”名字匹配
             mountPath: /var/lib/mysql # 挂载的Pod的目录
           - name: configmap
             mountPath: /etc/my.cnf
             subPath: my.cnf
             readOnly: true
      volumes:   # 挂载持久卷到Pod
        - name: mysql-persistent-storage # 持久卷名字， 与“volumMounts”名字匹配
          persistentVolumeClaim:
            claimName: mysql-pvc  # 持久卷申请名字
        - name: configmap
          configMap:
              name: mysql-configmap