主从数据库同步问题：Relay log read failure: Could not parse relay log event entry.

• • • 解决

mysql> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: XXX.XXX.XX.X
                  Master_User: root
                  Master_Port: 61011
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000280
          Read_Master_Log_Pos: 323835180
               Relay_Log_File: relay-log.000008
                Relay_Log_Pos: 286333492
        Relay_Master_Log_File: mysql-bin.000279
             Slave_IO_Running: Yes
            Slave_SQL_Running: No
              Replicate_Do_DB: 
          Replicate_Ignore_DB: 
           Replicate_Do_Table: 
       Replicate_Ignore_Table: 
      Replicate_Wild_Do_Table: 
  Replicate_Wild_Ignore_Table: 
                   Last_Errno: 1594
                   Last_Error: Relay log read failure: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave.
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 905542477
              Relay_Log_Space: 778371928
              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: NULL
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error: 
               Last_SQL_Errno: 1594
               Last_SQL_Error: Relay log read failure: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave.
  Replicate_Ignore_Server_Ids: 
             Master_Server_Id: 50

服务器异常导致数据库日志异常，同步失败

解决

通过show slave status\G;命令查看 Relay_Master_Log_File 和 Exec_Master_Log_Pos两个参数确定日志同步失败的位置, 重新配置主从

mysql> stop slave;
Query OK, 0 rows affected (0.00 sec)

mysql> reset slave all;
Query OK, 0 rows affected (0.07 sec)

mysql> change master to master_host='XXX.XX.X.X',master_port=61011,master_user='root',master_password='XXXXXXX', master_log_file='mysql-bin.000279',master_log_pos=905542477;
Query OK, 0 rows affected, 2 warnings (0.03 sec)

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

mysql> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Queueing master event to the relay log