启动mysql实例报错，查看 error log

## 错误信息
2018-08-31T10:38:36.945081Z 0 [ERROR] InnoDB: The Auto-extending innodb_system data file './ibdata1' is of a different size 768 pages (rounded down to MB) than specified in the .cnf file: initial 1536 pages, max 0 (relevant if non-zero) pages!

解决过程：

768/64=12

查看 my.cnf 文件 将
innodb_data_file_path = ibdata1:24M:autoextend

改为

innodb_data_file_path = ibdata1:12M:autoextend

再次启动成功！