mysql 主从搭建步骤

主库：

 开启log-bin参数，log-bin 参数修改需要重启服务器

--You can change the server_id value dynamically by issuing a statement like this:

SET GLOBAL server_id = 2;



--to enable binary logging using a log file name prefix of mysql-bin, and configure a server ID of 1, use these lines:

[mysqld]
log-bin=mysql-bin
server-id=1

--After making the changes, restart the server.

Note

The following options have an impact on this procedure:

• For the greatest possible durability and consistency in a replication setup using InnoDB with transactions, you should use innodb_flush_log_at_trx_commit=1 and sync_binlog=1 in the source's my.cnf file.

• Ensure that the skip_networking system variable is not enabled on your source. If networking has been disabled, the replica cannot communicate with the source and replication fails.

主库：

---创建账号
mysql> CREATE USER 'repl'@'%.example.com' IDENTIFIED BY 'password';
mysql> GRANT REPLICATION SLAVE ON *.* TO 'repl'@'%.example.com';


----flush all tables and block write statements by executing the FLUSH TABLES WITH READ LOCK statement:


mysql> FLUSH TABLES WITH READ LOCK;
mysql> SHOW MASTER STATUS\G
*************************** 1. row ***************************
             File: mysql-bin.000003
         Position: 73
     Binlog_Do_DB: test
 Binlog_Ignore_DB: manual, mysql
Executed_Gtid_Set: 3E11FA47-71CA-11E1-9E33-C80AA9429562:1-5
1 row in set (0.00 sec)

备份数据，把数据恢复到从库

主库操作

• On the source, released the read lock:

  mysql> UNLOCK TABLES;

从库：

Setting the Replica Configuration 

You can change the server_id value dynamically by issuing a statement like this:

SET GLOBAL server_id = 21;

If you are shutting down the replica server, you can edit the [mysqld] section of the configuration file to specify a unique server ID. For example:

[mysqld]
server-id=21

从库：

mysql> CHANGE MASTER TO
    ->     MASTER_HOST='source_host_name',
    ->     MASTER_USER='replication_user_name',
    ->     MASTER_PASSWORD='replication_password',
    ->     MASTER_LOG_FILE='recorded_log_file_name',
    ->     MASTER_LOG_POS=recorded_log_position;

1. 开始同步和检查状态:

   mysql> START SLAVE;
   mysql> STOP SLAVE;
   mysql> SHOW SLAVE STATUS\G

参考：

 MySQL :: MySQL 5.7 Reference Manual :: 16.1.2 Setting Up Binary Log File Position Based Replication