我有一个mysql服务器意外关闭。我使用的是安装了webmin/virtualmin的ubuntu16.04 lts。我在错误日志中没有看到任何错误。我只看到便条。
我有这个错误（/var/log/mysql/error.log）：

2018-10-25T03:03:01.744292Z 0 [Note] Giving 0 client threads a chance to die gracefully
2018-10-25T03:03:01.744322Z 0 [Note] Shutting down slave threads
2018-10-25T03:03:01.744329Z 0 [Note] Forcefully disconnecting 0 remaining clients
2018-10-25T03:03:01.744336Z 0 [Note] Event Scheduler: Purging the queue. 0 events
2018-10-25T03:03:03.744997Z 0 [Note] Binlog end
2018-10-25T03:03:03.747376Z 0 [Note] Shutting down plugin 'auth_socket'
2018-10-25T03:03:03.747390Z 0 [Note] Shutting down plugin 'ngram'
2018-10-25T03:03:03.747394Z 0 [Note] Shutting down plugin 'partition'
2018-10-25T03:03:03.747398Z 0 [Note] Shutting down plugin 'BLACKHOLE'
2018-10-25T03:03:03.747402Z 0 [Note] Shutting down plugin 'ARCHIVE'
2018-10-25T03:03:03.747405Z 0 [Note] Shutting down plugin 'MyISAM'
2018-10-25T03:03:03.747410Z 0 [Note] Shutting down plugin 'INNODB_SYS_VIRTUAL'
2018-10-25T03:03:03.747414Z 0 [Note] Shutting down plugin 'INNODB_SYS_DATAFILES'
2018-10-25T03:03:03.747417Z 0 [Note] Shutting down plugin 'INNODB_SYS_TABLESPACES'
2018-10-25T03:03:03.747420Z 0 [Note] Shutting down plugin 'INNODB_SYS_FOREIGN_COLS'
2018-10-25T03:03:03.747422Z 0 [Note] Shutting down plugin 'INNODB_SYS_FOREIGN'
2018-10-25T03:03:03.747425Z 0 [Note] Shutting down plugin 'INNODB_SYS_FIELDS'
2018-10-25T03:03:03.747428Z 0 [Note] Shutting down plugin 'INNODB_SYS_COLUMNS'
2018-10-25T03:03:03.747431Z 0 [Note] Shutting down plugin 'INNODB_SYS_INDEXES'
2018-10-25T03:03:03.747434Z 0 [Note] Shutting down plugin 'INNODB_SYS_TABLESTATS'
2018-10-25T03:03:03.747447Z 0 [Note] Shutting down plugin 'INNODB_SYS_TABLES'
2018-10-25T03:03:03.747457Z 0 [Note] Shutting down plugin 'INNODB_FT_INDEX_TABLE'
2018-10-25T03:03:03.747460Z 0 [Note] Shutting down plugin 'INNODB_FT_INDEX_CACHE'
2018-10-25T03:03:03.747463Z 0 [Note] Shutting down plugin 'INNODB_FT_CONFIG'
2018-10-25T03:03:03.747465Z 0 [Note] Shutting down plugin 'INNODB_FT_BEING_DELETED'
2018-10-25T03:03:03.747468Z 0 [Note] Shutting down plugin 'INNODB_FT_DELETED'
2018-10-25T03:03:03.747470Z 0 [Note] Shutting down plugin 'INNODB_FT_DEFAULT_STOPWORD'
2018-10-25T03:03:03.747473Z 0 [Note] Shutting down plugin 'INNODB_METRICS'
2018-10-25T03:03:03.747475Z 0 [Note] Shutting down plugin 'INNODB_TEMP_TABLE_INFO'
2018-10-25T03:03:03.747478Z 0 [Note] Shutting down plugin 'INNODB_BUFFER_POOL_STATS'
2018-10-25T03:03:03.747480Z 0 [Note] Shutting down plugin 'INNODB_BUFFER_PAGE_LRU'
2018-10-25T03:03:03.747483Z 0 [Note] Shutting down plugin 'INNODB_BUFFER_PAGE'
2018-10-25T03:03:03.747486Z 0 [Note] Shutting down plugin 'INNODB_CMP_PER_INDEX_RESET'
2018-10-25T03:03:03.747488Z 0 [Note] Shutting down plugin 'INNODB_CMP_PER_INDEX'
2018-10-25T03:03:03.747491Z 0 [Note] Shutting down plugin 'INNODB_CMPMEM_RESET'
2018-10-25T03:03:03.747493Z 0 [Note] Shutting down plugin 'INNODB_CMPMEM'
2018-10-25T03:03:03.747496Z 0 [Note] Shutting down plugin 'INNODB_CMP_RESET'
2018-10-25T03:03:03.747498Z 0 [Note] Shutting down plugin 'INNODB_CMP'
2018-10-25T03:03:03.747505Z 0 [Note] Shutting down plugin 'INNODB_LOCK_WAITS'
2018-10-25T03:03:03.747508Z 0 [Note] Shutting down plugin 'INNODB_LOCKS'
2018-10-25T03:03:03.747510Z 0 [Note] Shutting down plugin 'INNODB_TRX'
2018-10-25T03:03:03.747513Z 0 [Note] Shutting down plugin 'InnoDB'
2018-10-25T03:03:03.747596Z 0 [Note] InnoDB: FTS optimize thread exiting.
2018-10-25T03:03:03.747701Z 0 [Note] InnoDB: Starting shutdown...
2018-10-25T03:03:03.848008Z 0 [Note] InnoDB: Dumping buffer pool(s) to /var/lib/mysql/ib_buffer_pool
2018-10-25T03:03:03.848203Z 0 [Note] InnoDB: Buffer pool(s) dump completed at 181025 11:03:03
2018-10-25T03:03:05.258944Z 0 [Note] InnoDB: Shutdown completed; log sequence number 94132723
2018-10-25T03:03:05.260534Z 0 [Note] InnoDB: Removed temporary tablespace data file: "ibtmp1"
2018-10-25T03:03:05.260553Z 0 [Note] Shutting down plugin 'PERFORMANCE_SCHEMA'
2018-10-25T03:03:05.260585Z 0 [Note] Shutting down plugin 'CSV'
2018-10-25T03:03:05.260590Z 0 [Note] Shutting down plugin 'MRG_MYISAM'
2018-10-25T03:03:05.260594Z 0 [Note] Shutting down plugin 'MEMORY'
2018-10-25T03:03:05.260598Z 0 [Note] Shutting down plugin 'sha256_password'
2018-10-25T03:03:05.260601Z 0 [Note] Shutting down plugin 'mysql_native_password'
2018-10-25T03:03:05.260794Z 0 [Note] Shutting down plugin 'binlog'
2018-10-25T03:03:05.263651Z 0 [Note] /usr/sbin/mysqld: Shutdown complete

我需要帮助来解决这个问题。我已经和一些论坛和研究有关这类问题，但我没有任何运气找到一个解决办法。
每当服务关闭时，我都必须重新启动服务。