K8S搭建MySQL5.7集群(mysql5.7 + pvc + pv + configmap + headless service + statefuleset + nfs)

环境准备

• 安装docker
• 安装nexus3
• 安装nfs服务并创建PV

注：在NFS服务器上创建以下目录并确保目录内无任何文件。/opt/common/mysql5.7/mount/mysql-master-pv和/opt/common/mysql5.7/mount/mysql-slave-pv

创建PV

cat mysql-pv.yaml 
apiVersion: v1
kind: PersistentVolume
metadata:
  name: data-mysql-0
  labels:
    pv: data-mysql-0
spec:
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  nfs:
    path: /opt/common/mysql5.7/mount/mysql-master-pv
    server: 192.168.8.132
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: data-mysql-1
  labels:
    pv: data-mysql-1
spec:
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  nfs:
    path: /opt/common/mysql5.7/mount/mysql-slave-pv
    server: 192.168.8.132

创建PVC

cat mysql-pvc.yaml 
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: data-mysql-0
  namespace: default
  labels:
    app: data-mysql-0
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi
  selector:
    matchLabels:
      pv: data-mysql-0
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: data-mysql-1
  namespace: default
  labels:
    app: data-mysql-1
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi
  selector:
    matchLabels:
      pv: data-mysql-1

创建configmap

cat mysql-configMap.yaml 
apiVersion: v1
kind: ConfigMap
metadata:
  name: mysql
  labels:
    app: mysql
data:
  master.cnf: |
   [client]
    default-character-set=utf8
    [mysql]
    default-character-set=utf8
    [mysqld]
    # 打开binlog日志
    log-bin=bin-log
    max_connections=5000
   # 在容器里面需要设置下时区
    default-time-zone='+8:00'
    character-set-server=utf8
    init_connect='SET NAMES utf8'
    lower_case_table_names=1
    symbolic-links=0
    sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
    wait_timeout=31536000
    interactive_timeout=31536000
    slow_query_log = ON
    slow_query_log_file = /var/run/mysql/slow_query.log
    long_query_time = 1
  slave.cnf: |
    # Apply this config only on slaves.
    [client]
    default-character-set=utf8
    [mysql]
    default-character-set=utf8
    [mysqld]
    # 机器设置只读
    super-read-only
    max_connections=5000
    default-time-zone='+8:00'
    character-set-server=utf8
    init_connect='SET NAMES utf8'
    symbolic-links=0
    sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
    lower_case_table_names=1
    wait_timeout=31536000
    interactive_timeout=31536000
    slow_query_log = ON
    slow_query_log_file = /var/run/mysql/slow_query.log
    long_query_time = 1

创建statefulset

cat mysql-statefulset.yaml 
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: mysql
spec:
  selector:
    matchLabels:
      app: mysql
  serviceName: mysql
  replicas: 2
  template:
    metadata:
      labels:
        app: mysql
    spec:
      initContainers:
      - name: init-mysql
        image: mysql:5.7 
        command:
        - bash
        - "-c"
        - |
          set -ex
          # Generate mysql server-id from pod ordinal index.
          [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
          ordinal=${BASH_REMATCH[1]}
          echo [mysqld] > /mnt/conf.d/server-id.cnf
          # Add an offset to avoid reserved server-id=0 value.
          echo server-id=$((100 + $ordinal)) >> /mnt/conf.d/server-id.cnf
          # Copy appropriate conf.d files from config-map to emptyDir.
          if [[ $ordinal -eq 0 ]]; then
            cp /mnt/config-map/master.cnf /mnt/conf.d/
          else
            cp /mnt/config-map/slave.cnf /mnt/conf.d/
          fi
        volumeMounts:
        - name: conf
          mountPath: /mnt/conf.d
        - name: config-map
          mountPath: /mnt/config-map
      - name: clone-mysql
        image: yizhiyong/xtrabackup
        command:
        - bash
        - "-c"
        - |
          set -ex
          # Skip the clone if data already exists.
          [[ -d /var/lib/mysql/mysql ]] && exit 0
          # Skip the clone on master (ordinal index 0).
          [[ `hostname` =~ -([0-9]+)$ ]] || exit 1
          ordinal=${BASH_REMATCH[1]}
          [[ $ordinal -eq 0 ]] && exit 0
          # Clone data from previous peer.
          ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql
          # Prepare the backup.
          xtrabackup --prepare --target-dir=/var/lib/mysql
        volumeMounts:
        - name: data
          mountPath: /var/lib/mysql
          subPath: mysql
        - name: conf
          mountPath: /etc/mysql/conf.d
      containers:
      - name: mysql
        image: mysql:5.7 
        env:
#        - name: MYSQL_ALLOW_EMPTY_PASSWORD
#          value: "0"
        - name: MYSQL_ROOT_PASSWORD
          value: "xxxxxx"
        - name: MYSQL_ROOT_HOST
          value: "%"
        ports:
        - name: mysql
          containerPort: 3306
        volumeMounts:
        - name: data
          mountPath: /var/lib/mysql
          subPath: mysql
        - name: conf
          mountPath: /etc/mysql/conf.d
        resources:
          requests:
            cpu: 250m
            memory: 256Mi
        livenessProbe:
          exec:
            command: ["mysqladmin", "ping"]
          initialDelaySeconds: 30
          periodSeconds: 10
          timeoutSeconds: 5
        readinessProbe:
          exec:
            # Check we can execute queries over TCP (skip-networking is off).
            command: ["mysql","-uroot", "-h", "127.0.0.1","-pxxxxxx", "-e", "SELECT 1"]
          initialDelaySeconds: 5
          periodSeconds: 2
          timeoutSeconds: 1
      - name: xtrabackup
        image: yizhiyong/xtrabackup
        ports:
        - name: xtrabackup
          containerPort: 3307
        command:
        - bash
        - "-c"
        - |
          set -ex
          cd /var/lib/mysql
          # Determine binlog position of cloned data, if any.
          if [[ -f xtrabackup_slave_info ]]; then
            # XtraBackup already generated a partial "CHANGE MASTER TO" query

            # because we're cloning from an existing slave. (Need to remove the tailing semicolon!)
            mv xtrabackup_slave_info change_master_to.sql.in
            # Ignore xtrabackup_binlog_info in this case (it's useless).
            rm -f xtrabackup_slave_info
          elif [[ -f xtrabackup_binlog_info ]]; then
            # We're cloning directly from master. Parse binlog position.
            [[ `cat xtrabackup_binlog_info` =~ ^(.*?)[[:space:]]+(.*?)$ ]] || exit 1
            rm -f xtrabackup_binlog_info
            echo "CHANGE MASTER TO MASTER_LOG_FILE='${BASH_REMATCH[1]}',\
                  MASTER_LOG_POS=${BASH_REMATCH[2]}" > change_master_to.sql.in
          fi

          # Check if we need to complete a clone by starting replication.
          if [[ -f change_master_to.sql.in ]]; then
            echo "Waiting for mysqld to be ready (accepting connections)"
            until mysql -uroot -pxxxxxx -h 127.0.0.1 -e "SELECT 1"; do sleep 1; done
            echo "Initializing replication from clone position"
            mv change_master_to.sql.in change_master_to.sql.orig
            mysql -uroot -pxxxxxx -h 127.0.0.1 <<EOF
          $(<change_master_to.sql.orig),
            MASTER_HOST='mysql-0.mysql',
            MASTER_USER='root',
            MASTER_PASSWORD='xxxxxx',
            MASTER_CONNECT_RETRY=10;
          START SLAVE;
          EOF
          fi

          # Start a server to send backups when requested by peers.
          exec ncat --listen --keep-open --send-only --max-conns=1 3307 -c \
            "xtrabackup --backup --slave-info --stream=xbstream --host=127.0.0.1 --user=root --password=xxxxxx"
        volumeMounts:
        - name: data
          mountPath: /var/lib/mysql
          subPath: mysql
        - name: conf
          mountPath: /etc/mysql/conf.d
        resources:
          requests:
            cpu: 100m
            memory: 100Mi
      volumes:
      - name: conf
        emptyDir: {}
      - name: config-map
        configMap:
          name: mysql
  volumeClaimTemplates:
  - metadata:
      name: data
    spec:
      accessModes: ["ReadWriteOnce"]
      resources:
        requests:
          storage: 10Gi

创建headless service

cat mysql-service.yaml 
apiVersion: v1
kind: Service
metadata:
  name: mysql
  labels:
    app: mysql
spec:
  ports:
  - name: mysql
    port: 3306
  clusterIP: None
  selector:
    app: mysql
---
apiVersion: v1
kind: Service
metadata:
  name: mysql-read
  labels:
    app: mysql
spec:
  ports:
  - name: mysql
    port: 3306
  selector:
    app: mysql