基于docker的mysql8的主从复制

基于docker的mysql8的主从复制

建立mysql的docker镜像

• 构建docker镜像，其中数据卷配置内容在下面,结构目录以下

  version: '3.7'
  services: 
      db:
        # images 8.x
        image: mysql
        restart: always
        environment: 
          MYSQL_ROOT_PASSWORD: 456123
        command: 
          --default-authentication-plugin=mysql_native_password
          --character-set-server=utf8mb4
          --collation-server=utf8mb4_general_ci
          --explicit_defaults_for_timestamp=true
          --lower_case_table_names=1
        ports: 
          - 3309:3306
        volumes: 
          - ./data:/var/lib/mysql
          - ./my.cnf:/etc/my.cnf

配置mysql的主库

• 更新配置文件

  # Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU General Public License as published by
  # the Free Software Foundation; version 2 of the License.
  #
  # This program is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  # GNU General Public License for more details.
  #
  # You should have received a copy of the GNU General Public License
  # along with this program; if not, write to the Free Software
  # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  
  #
  # The MySQL  Server configuration file.
  #
  # For explanations see
  # http://dev.mysql.com/doc/mysql/en/server-system-variables.html
  
  [mysqld]
  
  pid-file        = /var/run/mysqld/mysqld.pid
  socket          = /var/run/mysqld/mysqld.sock
  datadir         = /var/lib/mysql
  secure-file-priv= NULL
  # Disabling symbolic-links is recommended to prevent assorted security risks
  symbolic-links=0
  
  # Custom config should go here
  # [必须]启用二进制日志
  log-bin=mysql-bin 
  # [必须]服务器惟一ID，默认是1  1~255
  server-id=1 
  sql_mode=STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION

• 配置操做

  1. 启动mysql

     docker-compose up -d

  2. 更新配置

     • 查看容器

       docker ps

       • 进入mysql交互

         docker exec -it 518a92715f6f /bin/bash

       • 登陆mysql

         mysql -u root -p

       • 配置

         #在主库上建立同步用户并受权
         CREATE USER 'replicate'@'112.74.41.236' IDENTIFIED BY '123456';
         GRANT REPLICATION SLAVE ON *.* TO 'replicate'@'112.74.41.236';
         FLUSH PRIVILEGES;
         #最后增长远程访问用户 并赋予全部权限，远程访问测试用
         CREATE USER antsdouble IDENTIFIED BY '123456';
         GRANT ALL ON *.* TO 'antsdouble'@'%';
         #用navicate12及以上能够不用修复修复远程登陆报报 caching_sha2_password异常
         # mysql8 用新的驱动  driver-class-name: com.mysql.cj.jdbc.Driver
         ALTER USER 'antsdouble'@'%' IDENTIFIED BY '123456' PASSWORD EXPIRE NEVER;
         ALTER USER 'antsdouble'@'%' IDENTIFIED WITH mysql_native_password BY '123456';
         FLUSH PRIVILEGES;
         #查询master的状态，此处File，Position数据在配置从库时用到
         show master status;

• 相关说明

  1. server-id是惟一的，主从不能相同，server-id为1表示mysq数据库为主数据库，server-id为2表示mysql的数据库为从数据库

  2. 为什么必须挂载到/etc/my.cnf 文件上，而不是/etc/mysql/my.cnf 文件上？由于mysql默认配置文件位置在/etc/mysql/my.cnf，挂在方式没法改变容器中文件内容，my.conf内容不会改变，my.cnf中没有咱们自定义的配置内容，启动mysql容器会报错

     lower_case_table_names：忽略表名、列名等数据结构的大小写（注意：不是每行记录内容的大小写！）。
     
     
     log-bin：开启二进制记录。这是为了主从复制而作的设置。本文使用RBR（Row-Based Replication）模式。
     
     slow_query_log=1：开启慢查询日志。若是某一条SQL执行的时间超过long_query_time设置的秒数，那么就记录下来。记录文件路径能够使用show variables;命令，在变量名是slow_query_log_file下查找到具体的日志文件路径。
     
     long_query_time=1：单位是秒。指若是某一条SQL语句执行时间超过1秒，就记录下来。必须开启慢查询日志了之后，此变量才能使用。
     
     log_error：开启错误日志。show variables like 'log_error'; 就能够查询到日志文件的路径。mysql的docker官方镜像若是设置别的取值会致使容器没法正常启动。

配置mysql的从库

• 更新配置文件

  # Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU General Public License as published by
  # the Free Software Foundation; version 2 of the License.
  #
  # This program is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  # GNU General Public License for more details.
  #
  # You should have received a copy of the GNU General Public License
  # along with this program; if not, write to the Free Software
  # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  
  #
  # The MySQL  Server configuration file.
  #
  # For explanations see
  # http://dev.mysql.com/doc/mysql/en/server-system-variables.html
  
  [mysqld]
  
  pid-file        = /var/run/mysqld/mysqld.pid
  socket          = /var/run/mysqld/mysqld.sock
  datadir         = /var/lib/mysql
  secure-file-priv= NULL
  # Disabling symbolic-links is recommended to prevent assorted security risks
  symbolic-links=0
  
  # Custom config should go here
  # [必须]启用二进制日志
  log-bin=mysql-bin 
  # [必须]服务器惟一ID，默认是1
  server-id=1 
  sql_mode=STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION

• 配置操做

  1. 进入交互模式，方法同主库

  2. 配置从库

     change master to master_host='112.74.41.236',master_port=3309,master_user='replicate',master_password='123456',master_log_file='binlog.000006',master_log_pos=3862;

     • 说明

       master_port：Master的端口号，指的是容器的端口号
       
       master_user：用于数据同步的用户
       
       master_password：用于同步的用户的密码
       
       master_log_file：指定 Slave 从哪一个日志文件开始复制数据，即上文中提到的 File 字段的值
       
       master_log_pos：从哪一个 Position 开始读，即上文中提到的 Position 字段的值
       
       master_connect_retry：若是链接失败，重试的时间间隔，单位是秒，默认是60秒

  3. 查看

     show slave status\G
     # 查询slave的状态，Slave_IO_Running及Slave_SQL_Running进程必须正常运行，即YES状态，不然都是错误的状态 错误能够在2标记处查看到缘由，也能够经过
     show slave status;

测试功能

• 主库添加一条数
• 在从库查看

常见问题

• 可能产生的缘由

  网络不通
  
  检查ip,端口
  
  密码不对
  
  检查是否建立用于同步的用户和用户密码是否正确
  
  pos不对
  
  检查Master的 Position

• Could not execute Update_rows event on table oa.bui_bill_sum; Can't find record in 'bui_bill_sum', Error_code: 1032; handler error HA_ERR_KEY_NOT_FOUND; the event's master log mysql-bin.000138, end_log_pos 160051747

  1. 解决，临时

     进入sql 执行
     STOP SLAVE; 
     SET GLOBAL sql_slave_skip_counter =1; #表示跳过一步错误，后面的数字可变 
     START SLAVE;

  2. 永久

     在my.cnf中配置
     slave-skip-errors = 1032 就会跳过全部的1032的错误,多个用逗号分隔

• mysql并无从my.cnf文件中更新server_id，既然这样就只能手动修改了

set global server_id=2; #此处的数值和my.cnf里设置的同样就行
slave start;

原文出处：https://www.cnblogs.com/ants_double/p/11763415.html