1)

change master导致的：

Last_IO_Error: error connecting to master 'repl1@IP:3306' -

retry-time: 60 retries

2) 在没有解锁的情况下停止slave进程：

mysql> stop slave;

ERROR 1192 (HY000): Can't execute the given command because you

have active locked tables or an active transaction

3)

change master语法错误，落下逗号

mysql> change master to

-> master_host='IP'

-> master_user='USER',

-> master_password='PASSWD',

-> master_log_file='mysql-bin.000002',

-> master_log_pos=106;

ERROR 1064 (42000): You have an error in your SQL syntax; check the

manual that corresponds to your MySQL server version for the right

syntax to use near 'master_user='USER',

master_password='PASSWD',

master_log_file='mysql-bin.000002' at line 3

4)

在没有停止slave进程的情况下change master

mysql> change master to master_host=‘IP',

master_user='USER', master_password='PASSWD',

master_log_file='mysql-bin.000001',master_log_pos=106;

ERROR 1198 (HY000): This operation cannot be performed with a

running slave; run STOP SLAVE first

5)

A B的server-id相同：

Last_IO_Error: Fatal error: The slave I/O thread stops because

master and slave have equal MySQL server

ids; these ids must be different for replication to work (or the

--replicate-same-server-id option must be used on

slave but this does not always make sense; please check the manual

before using it). 查看server-id

mysql> show variables like

'server_id'; 手动修改server-id

mysql> set global server_id=2;

#此处的数值和my.cnf里设置的一样就行 mysql> slave start;

6)change master之后，查看slave的状态，发现slave_IO_running

为NO

需要注意的是，做完上述操作之后最后重启mysql进程