这篇文章给大家分享的是有关使用reset master命令清空日志的示例分析的内容。小编觉得挺实用的，因此分享给大家做个参考，一起跟随小编过来看看吧。
今天看见主库binlog日志非常大，于是使用reset master命令清空日志
mysql> reset master;
Query OK, 0 rows affected (1 min 59.87 sec)
结果从库就报错了
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State:
Master_Host: 192.168.129.150
Master_User: replicat
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000312
Read_Master_Log_Pos: 2029035
Relay_Log_File: mysql-relay-bin.000945
Relay_Log_Pos: 2020198
Relay_Master_Log_File: mysql-bin.000312
Slave_IO_Running: No
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: 1
Exec_Master_Log_Pos: 2029035
Relay_Log_Space: 2029418
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: 1236
Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file'
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 2
Master_UUID: 124deecd-401b-11e6-b4e1-40f2e9de1e12
Master_Info_File: /data/DB/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp: 160808 11:08:49
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
1 row in set (0.00 sec)
再看下主库日志，已经重新开始了，不再是mysql-bin.000312
mysql> show master status;
+——————+———-+————–+——————+——————-+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+——————+———-+————–+——————+——————-+
| mysql-bin.000001 | 216484 | | | |
+——————+———-+————–+——————+——————-+
1 row in set (0.00 sec)
解决方法，重新设置slave进程
mysql> stop slave;
Query OK, 0 rows affected (0.01 sec)
mysql> change master to master_host='192.168.129.150',
-> master_user='replicat',
-> master_password='passw',
-> master_log_file='mysql-bin.000001',
-> master_log_pos=120;
Query OK, 0 rows affected, 2 warnings (0.05 sec)
mysql> start slave;
Query OK, 0 rows affected (0.02 sec)
mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.129.150
Master_User: replicat
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 310425
Relay_Log_File: mysql-relay-bin.000002
Relay_Log_Pos: 310588
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: 310425
Relay_Log_Space: 310761
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: 2
Master_UUID: 124deecd-401b-11e6-b4e1-40f2e9de1e12
Master_Info_File: /data/DB/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
1 row in set (0.00 sec)
问题虽然解决了，但是从报错记录来看
Read_Master_Log_Pos: 2029035
Relay_Log_Pos: 2020198
中间已经有一部分数据没有同步到从库，但因为这个数据库的OLAP系统，从业务了解没有大碍，所以不用担心数据不一致的情况，所以主库执行reset matser是一个非常危险的动作
感谢各位的阅读！
