mysql主从切换

1、修改配置文件

read-only=1（主库）

#read-only=1（备库）

 

2、查询从库状态

mysql> show processlist ;

 

mysql> show slave status G

 

 

3、查询主库状态

mysql> show processlist;

 

mysql> show master status G

*************************** 1. row ***************************

File: mysql-bin.000004

Position: 107

Binlog_Do_DB:

Binlog_Ignore_DB:

1 row in set (0.00 sec)

 

4、从库操作

mysql> STOP SLAVE IO_THREAD;

 

mysql> SHOW PROCESSLIST;

 

确保状态为：has read all relay log

 

mysql> show slave status G

 

 

5、查询主库状态

mysql> show master status G

 

 

6、从库变主库

mysql> STOP SLAVE;

 

mysql> RESET MASTER;

 

mysql> RESET SLAVE;

 

mysql> show master status G

*************************** 1. row ***************************

File: mysql-bin.000001

Position: 107

Binlog_Do_DB:

Binlog_Ignore_DB:

1 row in set (0.00 sec)

 

7、主库变从库

mysql> RESET MASTER;

Query OK, 0 rows affected (0.06 sec)

 

mysql> RESET SLAVE;

Query OK, 0 rows affected (0.03 sec)

 

mysql> CHANGE MASTER TO

-> MASTER_HOST='192.168.1.4',

-> MASTER_USER='repl',

-> MASTER_PASSWORD='chengce243',

-> MASTER_LOG_FILE='mysql-bin.000001',

-> MASTER_LOG_POS=107;

Query OK, 0 rows affected (0.05 sec)

 

mysql> start slave;

Query OK, 0 rows affected (0.00 sec)

 

8、重启主和从库

[root@localhost mysql]# service mysql restart

Shutting down MySQL….[ OK ]

Starting MySQL…………….[ OK ]

 

9、检查主从是否都正常

主库

SHOW PROCESSLIST;

show master status G

 

从库

SHOW PROCESSLIST;

start slave;

show slave status G