新设置mysql主从机，MySQL主从失败 错误Got fatal error 1236

                                                                          MySQL主从失败 错误Got fatal error 1236解决方法
新设置的主从mysql服务器, 报错, 错误如下:
show slave status错误:
mysql> show slave status\G
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 627806304
Relay_Log_File: mysql-relay-bin.000990
Relay_Log_Pos: 627806457
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: No
Slave_SQL_Running: Yes
Exec_Master_Log_Pos: 627806304
Relay_Log_Space: 627806663

......
Last_IO_Error: Got fatal error 1236 from master when  reading data from binary log:
'Client requested master to start  replication from impossible position'mysql错误日志:

tail var/lib/mysql/mysql-error.log
111010 17:35:49 [ERROR] Error reading packet from server: Client requested master
 to start replication from impossible position ( server_errno=1236)
111010 17:35:49 [ERROR] Slave I/O: Got fatal error 1236 from master when reading data
from binary log: 'Client requested master to start replication from impossible
position', Error_code: 1236
111010 17:35:49 [Note] Slave I/O thread exiting, read up to log 'mysql-bin.000001',
position 627806304

按照习惯, 先尝试必改position位置.

mysql> stop slave;
mysql> change master to master_log_file='mysql-bin.000001',master_log_pos=627625751;
mysql> start slave;错误依旧, 接下来登陆到主服务器查看binlog日志.
先按照错误点的标记去主服务器日志中查找:

[root@db1 ~]# mysqlbinlog --start-position=627655136 /var/lib/mysql/mysql-bin.000001
/*!40019 SET @@session.max_insert_delayed_threads=0*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at 4
#111010 13:31:19 server id 4 end_log_pos 106 Start: binlog v 4, server v 5.1.45-log
created 111010 13:31:19
# Warning: this binlog is either in use or was not closed properly.
BINLOG '
F1aTTg8EAAAAZgAAAGoAAAABAAQANS4xLjQ1LWxvZwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAEzgNAAgAEgAEBAQEEgAAUwAEGggAAAAICAgC
'/*!*/;
DELIMITER ;
# End of log file
ROLLBACK /* added by mysqlbinlog */;
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;没有看到这个位置.

[root@db1 ~]# mysqlbinlog /var/lib/mysql/mysql-bin.000001 > test.txt

less text.txt
看最后一部分
# at 627625495
#111010 16:35:46 server id 1 end_log_pos 627625631 Query thread_id=45613333
exec_time=32758 error_code=0
SET TIMESTAMP=1318289746/*!*/;
delete from freeshipping_bef_update where part='AR-4006WLM' and code=''
/*!*/;
# at 627625631
#111010 16:35:46 server id 1 end_log_pos 627625751 Query thread_id=45613333
exec_time=32758 error_code=0
SET TIMESTAMP=1318289746/*!*/;
delete from shippingFee_special where part='AR-4006WLM'
/*!*/;
DELIMITER ;
# End of log file
ROLLBACK /* added by mysqlbinlog */;
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;找到最接近错误标记627655136的一个position是627625631.

再回到slave机器上change master, 将postion指向这个位置.

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

mysql> change master to master_log_file='mysql-bin.000001',master_log_pos=627625631;
Query OK, 0 rows affected (0.06 sec)

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

mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Queueing master event to the relay log
Master_Host: 192.168.11.26
Master_User: rep
Master_Port: 3306
Connect_Retry: 10
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 25433767
Relay_Log_File: mysql-relay-bin.000003
Relay_Log_Pos: 630
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes

主从同步正常了！

 

附:主从的快速设置方法：

1、要主机上修改my.cnf

server-id = 1

log-bin       #开启记录地进制日志功能，很重要

2、在主机上增加一个帐号，分配从机的复制权限：

grant replication slave on *.*  to 'test'@'192.168.11.27'  identified by '123456';

3、用mysqldump导出数据，导入到从机

4、设置slave主机，修改my.cnf:

server-id = 2

其它slave从机以此类推，保证ID的唯一。

5、开启同步：

在从机中执行如下命令：

mysql> change master to mastart_host='192.168.11.26(主机IP)'，master_user='test',master_password='123456',master_log_file='mysql-bin.000001',master_log_pos=98;

mysql>slave start;

查看是否同步：

mysql>show slave status\G;

*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.11.26
                  Master_User: test
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 107
               Relay_Log_File: mysqld-relay-bin.000002
                Relay_Log_Pos: 253
        Relay_Master_Log_File: mysql-bin.000001
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          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: 107
              Relay_Log_Space: 410
              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: 1
1 row in set (0.00 sec)

如果：slave_io_runnung和slave_sql_running都为yes就表示成功。