m2复制m1配置；

m1先reset

RESET MASTER

m2里配置：

CHANGE MASTER TO MASTER_HOST='172.20.0.2', MASTER_USER='slave', MASTER_PASSWORD='123456', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=154;

START SLAVE

SHOW SLAVE STATUS 测试；

m1复制m2配置；

m2先rest

 RESET MASTER

m1里配置：

CHANGE MASTER TO MASTER_HOST='172.20.0.5', MASTER_USER='slave', MASTER_PASSWORD='123456', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=154;

START SLAVE

SHOW SLAVE STATUS 测试；