准备

• docker下载镜像使用mysql8（都2021了还有那么多mysql5教程我也是醉了）

docker pull mysql:8

获得my.cnf文件

• 先随便跑个mysql容器

docker run --privileged  \
--restart=unless-stopped \
--name mysql8-master     \
-p 13306:3306            \
-e MYSQL_ROOT_PASSWORD=123456 \
-d mysql:8

• 进入docker容器

docker exec -it mysql8-master /bin/bash 

• 在/etc/mysql/my.cnf获得my.cnf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

# Custom config should go here
!includedir /etc/mysql/conf.d/

• 删除mysql容器

docker stop mysql8-master
docker rm mysql8-master

运行mysql容器

• 运行master节点容器，启动应该会失败；但是没有关系！在/data/dockerMount/mysql/master/conf/my.cnf的路径下my.cnf是个文件夹，将其删除之后将上面得到的my.cnf文件放入即可

docker run --privileged  \
--restart=unless-stopped \
--name mysql8-master     \
-p 13306:3306            \
-v /data/dockerMount/mysql/master/conf/my.cnf:/etc/mysql/my.cnf \
-v /data/dockerMount/mysql/master/logs:/var/log/mysql \
-v /data/dockerMount/mysql/master/data:/var/lib/mysql  \
-e MYSQL_ROOT_PASSWORD=123456 \
-d mysql:8

• 重启master节点

docker restart mysql8-master

• 运行slave节点，和master节点一样的方法运行

docker run --privileged  \
--restart=unless-stopped \
--name mysql8-slave1     \
-p 13307:3306            \
-v /data/dockerMount/mysql/slave1/conf/my.cnf:/etc/mysql/my.cnf \
-v /data/dockerMount/mysql/slave1/logs:/var/log/mysql \
-v /data/dockerMount/mysql/slave1/data:/var/lib/mysql  \
-e MYSQL_ROOT_PASSWORD=123456 \
-d mysql:8

• 到此两个mysql容器运行起来了

读写分离

• 修改两个节点的my.cnf文件，server-id不同即可

#my.cnf文件修改
[mysqld]
server-id       = 1

配置主从

• 进入master节点查看file和position的值然后记下来

docker exec -it mysql8-master /bin/bash 
mysql -u root -p123456
show master status;
 File          | Position | 
+---------------+----------+
| binlog.000001 |      911 

• 配置用与同步的用户

alter user '用户名'@'%' identified by '密码' password expire never;

 alter user '用户名'@'%' identified with mysql_native_password by '密码';

flush privileges;

• 进入slave节点

docker exec -it mysql8-slave1 /bin/bash 
mysql -u root -p123456


change master to
master_host='主节点ip',
master_port=主节点端口,
master_user='主节点用户名',
master_password='主节点用户名密码',
master_log_file='binlog.000001',
master_log_pos=911;

 start slave;

• 如果配置错误，重新配置即可

stop slave;

• 查看状态

show slave status\G

• 看到以下两个yes即可

Slave_IO_Running: Yes
Slave_SQL_Running: Yes

参考文档

https://www.jianshu.com/p/5fc9145393eb