基于kubernetes部署MySQL主从环境

部署方式
通过部署mysql主从容器，配置主从pod之间数据同步。

配置数据库访问的密码

创建 Mysql 密码的 Secret
[root@k8s-master1 master]# kubectl create secret generic mysql-password --namespace=app --from-literal=mysql_root_password=root
secret/mysql-passowrd created
You have new mail in /var/spool/mail/root
[root@k8s-master1 master]# kubectl get secret -n app
NAME                                  TYPE                                  DATA   AGE
default-token-w6q98                   kubernetes.io/service-account-token   3      48d
ingress-nginx-admission               Opaque                                3      35d
ingress-nginx-admission-token-sqbvf   kubernetes.io/service-account-token   3      35d
ingress-nginx-token-bt7g2             kubernetes.io/service-account-token   3      35d
mysql-passowrd                        Opaque                                1      6s

先配置MySQL-Master服务
配置数据卷

[root@k8s-master1 master]# cat mysql-master-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-master-pvc
  namespace: app
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi
  storageClassName: nfs-client              #这里要换成你环境的storageClassName
  volumeMode: Filesystem
[root@k8s-master1 master]# kubectl apply -f mysql-master-pvc.yaml
[root@k8s-master1 master]# kubectl get pvc -n app
NAME                         STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
mysql-master-pvc             Bound    pvc-f2b5598c-4fd8-48f2-bc93-0e8c27e225ec   2Gi        RWO            nfs-client     10s

通过ConfiigMap配置MySQL的配置文件my.cnf

[root@k8s-master1 master]# cat my.cnf
[mysqld]
skip-host-cache
skip-name-resolve
datadir                = /var/lib/mysql
socket                 = /var/run/mysqld/mysqld.sock
secure-file-priv       = /var/lib/mysql-files
pid-file               = /var/run/mysqld/mysqld.pid
user                   = mysql
secure-file-priv       = NULL
server-id              = 1                              #master节点的server-id=1
log-bin                = master-bin
log_bin_index          = master-bin.index
binlog_do_db           = deploy_test
binlog_ignore_db       = information_sechema
binlog_ignore_db       = mysql
binlog_ignore_db       = performance_schema
binlog_ignore_db       = sys
binlog-format          = row

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

!includedir  /etc/mysql/conf.d/
[root@k8s-master1 master]# kubectl create cm mysql-master-cm --from-file=my.cnf -n app
configmap/mysql-master-cm created
[root@k8s-master1 master]# kubectl get cm -n app |grep mysql
mysql-master-cm            1      19s

配置Service服务

[root@k8s-master1 master]# cat mysql-master-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: mysql-master-svc
  namespace: app
  labels:
    app: mysql-master
spec:
  ports:
  - port: 3306
    name: mysql
    targetPort: 3306
    nodePort: 30306
  selector:
    app: mysql-master
  type: NodePort
  sessionAffinity: ClientIP
[root@k8s-master1 master]# kubectl apply -f mysql-master-svc.yaml
service/mysql-master-svc created

配置主节点pod启动的StatefulSet配置文件

[root@k8s-master1 master]# cat mysql-master-StatefulSet.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: mysql-master
  namespace: app
spec:
  selector:
    matchLabels:
      app: mysql-master
  serviceName: "mysql-master-svc"
  replicas: 1
  template:
    metadata:
      labels:
        app: mysql-master
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - args:
        - --character-set-server=utf8mb4
        - --collation-server=utf8mb4_unicode_ci
        - --lower_case_table_names=1
        - --default-time_zone=+8:00
        name: mysql
        # image: docker.io/library/mysql:8.0.34
        image: registry.cn-shenzhen.aliyuncs.com/xiaohh-docker/mysql:8.0.34
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: mysql-data
          mountPath: /var/lib/mysql
        - name: mysql-conf
          mountPath: /etc/my.cnf
          readOnly: true
          subPath: my.cnf
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              key: mysql_root_password
              name: mysql-password
      volumes:
      - name: mysql-data
        persistentVolumeClaim:
          claimName: mysql-master-pvc
      - name: mysql-conf
        configMap:
          name: mysql-master-cm
          items:
          - key: my.cnf
            mode: 0644
            path: my.cnf
[root@k8s-master1 master]# kubectl apply -f mysql-master-StatefulSet.yaml
statefulset.apps/mysql-master created

检查服务的启动情况

[root@k8s-master1 master]# kubectl get pods -n app -o wide |grep mysql
mysql-master-0                              1/1     Running   0              104s    10.10.36.73      k8s-node1     <none>           <none>

配置mysql-salve

配置PVC

[root@k8s-master1 slave]# cat mysql-slave-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-slave-pvc
  namespace: app
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi
  storageClassName: nfs-client
  volumeMode: Filesystem
[root@k8s-master1 slave]# kubectl apply -f mysql-slave-pvc.yaml
persistentvolumeclaim/mysql-slave-pvc created

配置ConfigMap

[root@k8s-master1 slave]# cat my.cnf
[mysqld]
skip-host-cache
skip-name-resolve
datadir                = /var/lib/mysql
socket                 = /var/run/mysqld/mysqld.sock
secure-file-priv       = /var/lib/mysql-files
pid-file               = /var/run/mysqld/mysqld.pid
user                   = mysql
secure-file-priv       = NULL
server-id              = 2                                #这个要修改
log-bin                = master-bin
log_bin_index          = master-bin.index
binlog_do_db           = deploy_test
binlog_ignore_db       = information_sechema
binlog_ignore_db       = mysql
binlog_ignore_db       = performance_schema
binlog_ignore_db       = sys
binlog-format          = row

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

!includedir  /etc/mysql/conf.d/
[root@k8s-master1 slave]# kubectl create cm mysql-slave-cm --from-file=my.cnf -n app
configmap/mysql-slave-cm created
You have new mail in /var/spool/mail/root
[root@k8s-master1 slave]# kubectl get cm -n app |grep mysql-slave-cm
mysql-slave-cm             1      13s

配置Service

[root@k8s-master1 slave]# cat mysql-slave-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: mysql-slave-svc
  namespace: app
  labels:
    app: mysql-slave
spec:
  ports:
  - port: 3306
    name: mysql
    targetPort: 3306
    nodePort: 30307
  selector:
    app: mysql-slave
  type: NodePort
  sessionAffinity: ClientIP
[root@k8s-master1 slave]# kubectl apply -f mysql-slave-svc.yaml
service/mysql-slave-svc created

创建MySQL的Pod

[root@k8s-master1 slave]# cat mysql-slave-StatefulSet.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: mysql-slave
  namespace: app
spec:
  selector:
    matchLabels:
      app: mysql-slave
  serviceName: "mysql-master-svc"
  replicas: 1
  template:
    metadata:
      labels:
        app: mysql-slave
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - args:
        - --character-set-server=utf8mb4
        - --collation-server=utf8mb4_unicode_ci
        - --lower_case_table_names=1
        - --default-time_zone=+8:00
        name: mysql
        # image: docker.io/library/mysql:8.0.34
        image: registry.cn-shenzhen.aliyuncs.com/xiaohh-docker/mysql:8.0.34
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: mysql-data
          mountPath: /var/lib/mysql
        - name: mysql-conf
          mountPath: /etc/my.cnf
          readOnly: true
          subPath: my.cnf
        env:
        - name: MYSQL_ROOT_PASSWORD
          valueFrom:
            secretKeyRef:
              key: mysql_root_password
              name: mysql-password
      volumes:
      - name: mysql-data
        persistentVolumeClaim:
          claimName: mysql-slave-pvc
      - name: mysql-conf
        configMap:
          name: mysql-slave-cm
          items:
          - key: my.cnf
            mode: 0644
            path: my.cnf
[root@k8s-master1 slave]# kubectl apply -f mysql-slave-StatefulSet.yaml
statefulset.apps/mysql-slave created
[root@k8s-master1 slave]# kubectl get pods -n app -o wide |grep mysql
mysql-master-0                              1/1     Running   0               14m     10.10.36.73      k8s-node1     <none>           <none>
mysql-slave-0                               1/1     Running   0               38s     10.10.36.74      k8s-node1     <none>           <none>

主从POD都创建完成了，咱们登录验证一下，并配置一下主从同步

[root@k8s-master1 slave]# kubectl exec -it mysql-master-0 -n app -- mysql -uroot -proot
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.34 MySQL Community Server - GPL

Copyright (c) 2000, 2023, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

在从节点执行，配置主从关系

mysql> change master to master_host='mysql-master-0.mysql-master-svc.app.svc.cluster.local',
    -> master_port=3306, master_user='root', master_password='root', master_log_file='master-bin.000003',
    -> master_log_pos=157,master_connect_retry=30,get_master_public_key=1;
Query OK, 0 rows affected, 11 warnings (0.03 sec)
master_host：这个参数是master的地址，kubernetes 提供的解析规则是 pod 名称.service名称.命名空间.svc.cluster.local，所以 master 的 mysql 地址是 deploy-mysql-master-0.deploy-mysql-master-svc.deploy-test.svc.cluster.local
master_port：主节点的 MySQL 端口，没改默认 3306
master_user：登录到主节点的 mysql 用户
master_password：登录到主节点的用户密码
master_log_file：之前查看 mysql 主节点状态时的 file 字段
master_log_pos：之前查看 mysql 主节点状态时的 Position 字段
master_connect-retry：主节点重连时间
get_master_public_key：连接主 mysql 的公钥获取方式

启动 slave

mysql> start slave;
Query OK, 0 rows affected, 1 warning (0.01 sec)

查看slave的状态

mysql> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for source to send event
                  Master_Host: mysql-master-0.mysql-master-svc.app.svc.cluster.local
                  Master_User: root
                  Master_Port: 3306
                Connect_Retry: 30
              Master_Log_File: master-bin.000003
          Read_Master_Log_Pos: 157
               Relay_Log_File: mysql-slave-0-relay-bin.000002
                Relay_Log_Pos: 327
        Relay_Master_Log_File: master-bin.000003
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

在主节点创建一个数据库验证一下主从同步情况