今天在配置mysql replication的時候，修改完my.cnf文件，然后重啟mysql service ,當執行下列命名的時候報錯：
change master to master_host='127.0.0.1',
master_user='usertest',master_password='usertest', master_log_file='mysql-bin-000002', master_log_pos=8;
ERROR 1201 (HY000): Could not initialize master info structure; more error messages can be found in the MySQL error log
check錯誤日志文件 mysqld.log ,發現有如下錯誤：
140123 12:48:18 [ERROR] Error reading master configuration
140123 12:48:18 [ERROR] Failed to initialize the master info structure
后來檢查發現在mysql數據庫文件夾下面有個 空的master.info 文件（有時候還有個空的relay-log.info），問題在這里。
解決辦法：
method 1 :
mysql> stop slave ;
mysql> reset salve ;
then change master
mysql> change master to master_host='127.0.0.1', master_user='usertest', master_pass
word='usertest', master_log_file='mysql-bin-000002', master_log_pos=8;
Query OK, 0 rows affected (0.11 sec)
method 2 :
rm -f /var/lib/mysql/master.info
then
mysql> change master to master_host='127.0.0.1', master_user='usertest', master_pass
word='usertest', master_log_file='mysql-bin-000002', master_log_pos=12;
Query OK, 0 rows affected (0.11 sec)
最后檢查MySQL主從同步是否正常
mysql> start slave ;
Query OK, 0 rows affected (0.01 sec)
mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 127.0.0.1
Master_User: korea_slave
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: bin-update-log.000009
Read_Master_Log_Pos: 1551
Relay_Log_File: mysqld-relay-bin.000002
Relay_Log_Pos: 1702
Relay_Master_Log_File: bin-update-log.000009
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB: tkglobal,tktest
Replicate_Ignore_DB: local
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: 1551
Relay_Log_Space: 1859
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1260119
1 row in set (0.00 sec)
