1、首先建立兩個檔案my-m.cnf（主庫配置） 、my-s.cnf（從庫配置）
my-m.cnf 內容如下

# Copyright (c) 2014, 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 Community Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

[client]
port        = 3306
socket      = /var
 
/run/mysqld/mysqld.sock

[mysqld_safe]
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
lc-messages-dir = /usr/share/mysql
explicit_defaults_for_timestamp

log-bin = mysql-bin 
server-id = 1 

# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
#bind-address   = 127.0.0.1

#log-error  = /var/log/mysql/error.log

# Recommended in standard MySQL setup
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

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

# * IMPORTANT: Additional settings that can override those from this file!
#   The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/

主要是這兩行，只需要在原來的配置裡面加上就行

log-bin = mysql-bin 
server-id = 1 

my-s.cnf 內容如下

# Copyright (c) 2014, 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 Community Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

[client]
port        = 3306
socket      = /var/run/mysqld/mysqld.sock

[mysqld_safe]
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
lc-messages-dir = /usr/share/mysql
explicit_defaults_for_timestamp

log-bin = mysql-bin 
server-id = 2

# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
#bind-address   = 127.0.0.1

#log-error  = /var/log/mysql/error.log

# Recommended in standard MySQL setup
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

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

# * IMPORTANT: Additional settings that can override those from this file!
#   The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/

同樣，主要的是這兩行

log-bin = mysql-bin 
server-id = 2

2、OK，有了配置檔案，就可以啟動mysql了，先啟動主庫

$ docker run -d -e MYSQL_ROOT_PASSWORD=admin --name mysql-master -v /soft/my-m.cnf:/etc/mysql/my.cnf -p 3307:3306 mysql

3、啟動從庫

$ docker run -d -e MYSQL_ROOT_PASSWORD=admin --name mysql-slave -v /soft/my-s.cnf:/etc/mysql/my.cnf -p 3308:3306 mysql

4、連線主庫，並執行以下命令，建立一個使用者用來同步資料

$ GRANT REPLICATION SLAVE ON *.* to 'backup'@'%' identified by '123456';

5、檢視主庫狀態

$ show master status;

記住File、Position的值，如果沒查到資料，請檢查第一、第二步，配置問題。
我查出來的是mysql-bin.000004、312

6、連線到從庫，執行以下命令，設定主庫連結

$ change master to master_host='121.32.32.54',master_user='backup',master_password='123456',
master_log_file='mysql-bin.000004',master_log_pos=312,master_port=3307;

7、啟動同步

$ start slave;

8、檢視同步狀態

$ show slave status

如果看到Waiting for master send event.. 什麼的就成功了，你現在在主庫上的修改，都會同步到從庫上