Mysql Master error :Failed to initialize the master info structure

今天在配置mysql replication的時候，修改完my.cnf文件，然後重啓mysql service ,當執行下列命名的時候報錯：

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;  

ERROR 1201 (HY000): Could not initialize master info structure; more error messages can be found in the MySQL error log  

check錯誤日誌文件 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

後來檢查發現在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），問題在這裏。

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)  

at last ,check the replicatin to see if config well

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)