一、先修改配置文件 服务器A（192.168.1.254）配置如下

log-bin   = mysql-bin
server-id = 1 
expire-logs-days  = 100 
replicate-do-db   = test
binlog-ignore-db  = mysql
binlog-ignore-db  = information_schema
auto-increment-increment = 2 
auto-increment-offset = 1

服务器B（192.168.1.252）配置

log-bin   = mysql-bin
server-id = 2
expire-logs-days  = 100
replicate-do-db   = test
binlog-ignore-db  = mysql
binlog-ignore-db  = information_schema
auto-increment-increment = 2
auto-increment-offset = 2

两台服务器都重启

mysql> service mysqld restart

注：二都只有server-id不同和 auto-increment- offset不同 auto-increment-offset是用来设定数据库中自动增长的起点的，回为这两能服务器都设定了一次自动增长值2，所以它们的起点必须得不同，这样才能避免两台服务器数据同步时出现主键冲突 replicate-do-db 指定同步的数据库，我们只在两台服务器间同步test数据库 另：auto-increment-increment的值应设为整个结构中服务器的总数，本案例用到两台服务器，所以值设为2 二、同步数据 本文是用test做的实验，导出将test.sql文件从254服务器拷贝到252服务器 备份数据前先锁表，保证数据一致性

mysql> FLUSH TABLES WITH READ LOCK;
# mysqldump -uroot -p123456 test> /tmp/test.sql; 
mysql> UNLOCK TABLES;
 scp /tmp/test.sql root@192.168.1.252:/tmp

三、相互授权用户(在A服务器授权一个允许B访问的用户，反之亦然) 在服务器A（192.168.1.254）上

mysql> GRANT REPLICATION SLAVE ON *.* TO 'mysync'@'192.168.1.252' IDENTIFIED BY PASSWORD '123456';
mysql> flush privileges;

在服务器B（192.168.1.252）上

mysql> GRANT REPLICATION SLAVE ON *.* TO 'mysync'@'192.168.1.254' IDENTIFIED BY PASSWORD '123456';
mysql> flush privileges;

四、互告bin-log信息 在服务器A（192.168.1.254）

mysql> show master status;
+------------------+----------+--------------+--------------------------+
| File     | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+--------------------------+
| mysql-bin.000006 |      106 |      | mysql,information_schema |
+------------------+----------+--------------+--------------------------+

在服务器B（192.168.1.252）

mysql> show master status;
+------------------+----------+--------------+--------------------------+
| File     | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+--------------------------+
| mysql-bin.000008 |      192 |      | mysql,information_schema |
+------------------+----------+--------------+--------------------------+

在A服务器（192.168.1.254）上执行

 
mysql> change master to master_host='192.168.1.252',master_user='mysync',master_password='123456',master_log_file='mysql-bin.000008',master_log_pos=192;

在B服务器（192.168.1.252）上执行

mysql> change master to master_host='192.168.1.254',master_user='mysync',master_password='123456',master_log_file='mysql-bin.000006',master_log_pos=106;

五、在两服务器都执行以下命令

mysql> start slave;

六、查看状态

mysql> show slave status\G

A服务器（192.168.1.254）状态如下：

 Slave_IO_State: Waiting for master to send event
  Master_Host: 192.168.1.252
  Master_User: mysync
  Master_Port: 3306
Connect_Retry: 60
      Master_Log_File: mysql-bin.000008
  Read_Master_Log_Pos: 192
       Relay_Log_File: mysqld-relay-bin.000009
Relay_Log_Pos: 337
Relay_Master_Log_File: mysql-bin.000008
     Slave_IO_Running: Yes
    Slave_SQL_Running: Yes
      Replicate_Do_DB: test

B服务器（192.168.1.252）状态如下：

  Slave_IO_State: Waiting for master to send event
  Master_Host: 192.168.1.254
  Master_User: mysync
  Master_Port: 3306
Connect_Retry: 60
      Master_Log_File: mysql-bin.000006
  Read_Master_Log_Pos: 106
       Relay_Log_File: mysqld-relay-bin.000014
Relay_Log_Pos: 251
Relay_Master_Log_File: mysql-bin.000006
     Slave_IO_Running: Yes
    Slave_SQL_Running: Yes
      Replicate_Do_DB: test

当看到了两个yes，即： Slave_IO_Running: Yes Slave_SQL_Running: Yes 说明已经配置成功了