MySQL是一種常見的關系型數據庫管理系統，在Linux中使用廣泛。啟動MySQL時，系統會自動生成啟動日志。那么，MySQL啟動日志在哪里呢？下面將為大家詳細介紹。

$ sudo systemctl start mysqld

以上是啟動MySQL的命令。在Linux中，MySQL啟動日志會記錄在MySQL的錯誤日志中，錯誤日志默認存放在/var/log/mysql/error.log文件中。可以使用以下命令查看該文件：

$ sudo cat /var/log/mysql/error.log

如果MySQL啟動失敗，可以查看錯誤日志以獲取有關錯誤的詳細信息。在錯誤日志中，MySQL將記錄啟動過程中發生的任何錯誤、警告和其他信息。以下是錯誤日志中可能出現的信息示例：

2021-08-04T11:13:08.187011Z 0 [Note] InnoDB: using atomic writes
2021-08-04T11:13:08.187062Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2021-08-04T11:13:08.187066Z 0 [Note] InnoDB: Uses event mutexes
2021-08-04T11:13:08.187069Z 0 [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
2021-08-04T11:13:08.187073Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.11
2021-08-04T11:13:08.187076Z 0 [Note] InnoDB: Using Linux native AIO
2021-08-04T11:13:08.187361Z 0 [Note] InnoDB: Number of pools: 1
2021-08-04T11:13:08.187533Z 0 [Note] InnoDB: Using CPU crc32 instructions
2021-08-04T11:13:08.188472Z 0 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M
2021-08-04T11:13:08.196688Z 0 [Note] InnoDB: Completed initialization of buffer pool
2021-08-04T11:13:08.199697Z 0 [Note] InnoDB: 128 out of 128 rollback segments are active.
2021-08-04T11:13:08.199712Z 0 [Note] InnoDB: Creating shared tablespace for temporary tables
2021-08-04T11:13:08.199767Z 0 [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
2021-08-04T11:13:08.262776Z 0 [Note] InnoDB: File './ibtmp1' size is now 12 MB.
2021-08-04T11:13:08.263773Z 0 [Note] InnoDB: Waiting for purge to start
2021-08-04T11:13:08.324804Z 0 [Note] InnoDB: 10.5.9 started; log sequence number 3611191; transaction id 21

在上述示例中，錯誤日志顯示了InnoDB存儲引擎的初始化情況，以及創建和初始化臨時表空間的情況。

總之，在Linux中，MySQL啟動日志存儲在錯誤日志文件中。通過查看錯誤日志，可以了解MySQL啟動過程中的任何錯誤、警告和其他信息。希望本文對您有所幫助。