--演示环境，同一主机上的2个实例，主3406，从3506

--当前版本，注：master账户表明是对主库进行相关操作，slave则是对从库进行相关操作

master@localhost[(none)]> show variables like'version';
+---------------+------------+
Variable_name   Value
+---------------+------------+
version         5.6.12-log
+---------------+------------+
--主库上的记录

master@localhost[test]> select * from tb1;
+------+-------+
id     name
+------+-------+
1   robin
+------+-------+
--从库上的记录

slave@localhost[test]> select * from tb1;
+------+-------+
id     name
+------+-------+
1   robin
+------+-------+
--当前从库上的状态信息

slave@localhost[test]> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.177
Master_User: repl
Master_Port: 3406
Connect_Retry: 60
Master_Log_File: inst3406bin.000001
Read_Master_Log_Pos: 3296006
Relay_Log_File: relay-bin.000002
Relay_Log_Pos: 811
Relay_Master_Log_File: inst3406bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB: test,sakila   --仅复制了test以及sakila数据库

Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 3296006
Relay_Log_Space: 978
--主库上复制账户的信息

master@localhost[test]> show grants for'repl'@'192.168.1.177';
+----------------------------------------------------------------------------------------------------------------+
Grants for repl@192.168.1.177
+----------------------------------------------------------------------------------------------------------------+
GRANT REPLICATION SLAVE ON *.* TO'repl'@'192.168.1.177' IDENTIFIED BYPASSWORD'*A424E797037BF191C5C2038C039'
+----------------------------------------------------------------------------------------------------------------+
--修改复制账户密码

master@localhost[test]> GRANT REPLICATION SLAVE ON *.* TO'repl'@'192.168.1.177' IDENTIFIED BY'replpwd';
--如下查询密码已更改

master@localhost[test]> selectuser,host,passwordfrom mysql.userwhereuser='repl';
+------+---------------+-------------------------------------------+
user   host            password
+------+---------------+-------------------------------------------+
repl   192.168.1.177   *4A04E4FD524292A79E3DCFEBBD46094478F178EF
+------+---------------+-------------------------------------------+
--更新记录

master@localhost[test]> insertinto tb1 values(2,'fred');
--重库上可以查询到刚刚被更新的记录

slave@localhost[test]> select * from tb1;
+------+-------+
id     name
+------+-------+
1   robin
2   fred
+------+-------+
slave@localhost[test]> stop slave;
Query OK, 0 rows affected (0.02 sec)
slave@localhost[test]> start slave;
Query OK, 0 rows affected (0.01 sec)
--再次查看状态出现了错误提示

slave@localhost[test]> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Connecting to master
Master_Host: 192.168.1.177
Master_User: repl
Master_Port: 3406
Connect_Retry: 60
Master_Log_File: inst3406bin.000001
Read_Master_Log_Pos: 3296438
Relay_Log_File: relay-bin.000002
Relay_Log_Pos: 1243
Relay_Master_Log_File: inst3406bin.000001
Slave_IO_Running: Connecting
Slave_SQL_Running: Yes
Replicate_Do_DB: test,sakila
....................
Last_IO_Errno: 1045
Last_IO_Error: error connecting to master 'repl@192.168.1.177:3406' - retry-time: 60  retries: 1
--更改重库连接密码，该信息记录在从库master.info文件中                

slave@localhost[test]> stop slave;
slave@localhost[test]> change master to
-> master_user='repl',
-> master_password='replpwd';
Query OK, 0 rows affected, 2 warnings (0.00 sec)
--修改密码后，从库状态正常，以下检查结果不再列出

slave@localhost[test]> start slave;
--查看master.info，密码已更改且为名文
slave@localhost[(none)]> system grep repl /data/inst3506/data3506/master.info
repl
replpwd

master@localhost[test]> GRANT REPLICATION SLAVE ON *.* TO'repl2'@'192.168.1.177' IDENTIFIED BY'Repl2';
Query OK, 0 rows affected (0.00 sec)
slave@localhost[test]> stop slave;
Query OK, 0 rows affected (0.28 sec)
master@localhost[test]> insertinto tb1 values(3,'jack');
Query OK, 1 row affected (0.00 sec)
slave@localhost[test]> change master to
-> MASTER_USER='repl2',
-> MASTER_PASSWORD='Repl2';
Query OK, 0 rows affected, 2 warnings (0.01 sec)
slave@localhost[test]> system more /data/inst3506/data3506/master.info
23
inst3406bin.000001
3294834
192.168.1.177
repl2
Repl2
3406
..........
slave@localhost[test]> start slave;
Query OK, 0 rows affected (0.01 sec)
slave@localhost[test]> select * from tb1 where id=3;
+------+------+
id     name
+------+------+
3   jack
+------+------+
1 row inset (0.00 sec)
slave@localhost[(none)]> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.177
Master_User: repl2
Master_Port: 3406
Connect_Retry: 60
Master_Log_File: inst3406bin.000001
Read_Master_Log_Pos: 3296871
Relay_Log_File: relay-bin.000002
Relay_Log_Pos: 501
Relay_Master_Log_File: inst3406bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB: test,sakila

--转自