MySQL主从搭建（多主一从）的实现思路与步骤

[mysqld]
lower_case_table_names = 1 # 表名不区分大小写
server-id = 100
log_bin = mysql-bin  #开始binlog记录
binlog_format = MIXED 
#每次事务提交，MySQL都会把binlog刷下去，是最安全但是性能损耗最大的设置。
#这样的话，在数据库所在的主机操作系统损坏或者突然掉电的情况下，系统才有可能丢失1个事务的数据
#但是binlog虽然是顺序IO，但是设置sync_binlog=1，多个事务同时提交，
#同样很大的影响MySQL和IO性能。按需设置。
sync_binlog = 1 
# 二进制日志自动删除/过期的天数。默认值为0，表示不自动删除。
expire_logs_days = 7
#binlog_cache_size = 128m
#max_binlog_cache_size = 512m
#max_binlog_size = 256M
# 需要同步库
binlog-do-db = dev
# 不需要同步库
binlog-ignore-db = mysql
binlog_ignore_db = information_schema
binlog_ignore_db = performation_schema
binlog_ignore_db = sys
datadir=/var/lib/mysql

# mysql -uroot -p 
# password: xxxxxx
# mysql> GRANT REPLICATION SLAVE ON *.* TO 'slave'@'%' IDENTIFIED BY 'root1234';
# mysql> flush privileges;
# quit;
# systemctl restart mysqld;
# show master status \G
#*************************** 1. row ***************************
             File: mysql-bin.000001
         Position: 886
     Binlog_Do_DB: dev
 Binlog_Ignore_DB: mysql,information_schema,performation_schema,sys
Executed_Gtid_Set: 
1 row in set (0.00 sec)

[mysqld]
lower_case_table_names = 1 # 表名不区分大小写
server-id = 200
log_bin = mysql-bin  #开始binlog记录
binlog_format = MIXED 
#每次事务提交，MySQL都会把binlog刷下去，是最安全但是性能损耗最大的设置。
#这样的话，在数据库所在的主机操作系统损坏或者突然掉电的情况下，系统才有可能丢失1个事务的数据
#但是binlog虽然是顺序IO，但是设置sync_binlog=1，多个事务同时提交，
#同样很大的影响MySQL和IO性能。按需设置。
sync_binlog = 1 
# 二进制日志自动删除/过期的天数。默认值为0，表示不自动删除。
expire_logs_days = 7
#binlog_cache_size = 128m
#max_binlog_cache_size = 512m
#max_binlog_size = 256M
# 需要同步库
binlog-do-db =dev
# 不需要同步库
binlog-ignore-db = mysql
binlog_ignore_db = information_schema
binlog_ignore_db = performation_schema
binlog_ignore_db = sys
datadir=/var/lib/mysql

# mysql -uroot -p 
# password: xxxxxx
# mysql> GRANT REPLICATION SLAVE ON *.* TO 'slave'@'%' IDENTIFIED BY 'root1234';
# mysql> flush privileges;
# quit;
# systemctl restart mysqld;
# show master status \G
#*************************** 1. row ***************************
             File: mysql-bin.000001
         Position: 154
     Binlog_Do_DB: dev
 Binlog_Ignore_DB: mysql,information_schema,performation_schema,sys
Executed_Gtid_Set: 
1 row in set (0.00 sec)

[mysqld]
lower_case_table_names = 1 # 表名不区分大小写 
server-id = 300
master_info_repository = table
relay_log_info_repository = table 
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock  
symbolic-links=0 
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

# mysql -uroot -p 
# password: xxxxxx
# 设置主库信息
# mysql> CHANGE MASTER TO  
# ->MASTER_HOST='192.168.194.3',
# ->MASTER_PORT=3306, MASTER_USER='slave', 
# ->MASTER_PASSWORD='root1234',
# ->MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=886 for channel '100';
# mysql> CHANGE MASTER TO  
# ->MASTER_HOST='192.168.194.4',
# ->MASTER_PORT=3306, MASTER_USER='slave', 
# ->MASTER_PASSWORD='root1234',
# ->MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=154  for channel '200';
# 设置主库信息
# mysql> flush privileges;
# start slave;
# mysql>show slave status \G  

CREATE TABLE `t_user`  (
  `id` varchar(32) NOT NULL COMMENT '主键ID',
  `name` varchar(32) CHARACTER SET utf8mb4 NULL COMMENT '用户名称',
  `code` varchar(32) CHARACTER SET utf8mb4 NULL COMMENT '用户编码',
  `phone_number` varchar(300) CHARACTER SET utf8mb4 NULL COMMENT '电话号码',
  `create_date` datetime NULL COMMENT '创建时间',
  `update_date` datetime NULL COMMENT '修改时间',
  PRIMARY KEY (`id`)
) COMMENT = '用户信息表';
INSERT INTO t_user (`id`, `name`, `code`, `phone_number`, `create_date`, `update_date`) 
VALUES ('userId_4', '张三', '123456789', '123456789632', '2020-04-27 22:05:00', '2020-04-27 22:05:00');

SELECT * FROM t_user;
------+--------+----------+--------------+---------------------+-------------+
| id       | name   | code     | phone_number | create_date  | update_date |
+-------+--------+----------+--------------+---------------------+----------+
| userId_4 | 张三 |123456789|123456789632|2020-04-27 22:05:00|2020-04-27 22:05:00