转载自：https://www.cnblogs.com/xiaoit/p/3977843.html
1、主库需改配置文件，在/etc/my.cnf中添加：
port = 3306
log_bin = /var/lib/mysql/mysql-binlog
server-id = 1 //只要主从不一样就行
binlog_do_db = test//要做同步的数据库名字，可以是多个数据库，之间用分号分割。
2、从库的配置文件中添加
server-id = 2
master-host = 10.4.14.168 //主库的ip地址
master-user = gechong //同步的mysql账号
master-password = gechong //同步的mysql密码
master-port = 3306
master-connect-retry = 5
replicate-do-db = test //数据库名
3、分别重启服务，登陆数据库。
4、主库上创建复制用户
mysql> GRANT REPLICATION SLAVE,REPLICATION CLIENT ON *.* TO gechong@'%' IDENTIFIED BY 'gechong';
5、在主库上执行
mysql> show master status;
+---------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+---------------+----------+--------------+------------------+
| binlog.000003 | 412 | | |
+---------------+----------+--------------+------------------+
1 row in set (0.00 sec)
6、从库上执行
mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.4.14.168
Master_User: gechong
Master_Port: 3306
Connect_Retry: 5
Master_Log_File: mysql-binlog.000001
Read_Master_Log_Pos: 325
Relay_Log_File: mysqld-relay-bin.000002
Relay_Log_Pos: 473
Relay_Master_Log_File: mysql-binlog.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB: test
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 325
Relay_Log_Space: 629
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
1 row in set (0.00 sec)
可以看到：Slave_IO_Running | Slave_SQL_Running两个值都是YES，说明配置成功了。可以在主库的test库里执行DML或者DDL验证下。
如果同步不成功：
1：停掉从库
mysql> slave stop
2：主库上找到日志和位置
mysql> show master status;
3：手动同步
mysql> change master to
> master_host='master_ip',
> master_user='gechong',
> master_password='gechong',
> master_port=3306,
> master_log_file='mysql-bin.000020',
> master_log_pos=135617781;
1 row in set (0.00 sec)
4：启动从库
mysql> slave start;
1 row in set (0.00 sec)
如果有异常需要跳过：
mysql>slave stop;
>SET GLOBAL sql_slave_skip_counter = 1;
>slave start;
主从搭建一般步骤：
