sudo systemctl start mysqld
Job for mysqld.service failed because the control process exited with error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.
sudo systemctl status mysqld
https://i.imgur.com/KtjreBu.png
journalctl -xe
https://i.imgur.com/ryid027.png
mysqld.log 里面的日志显示: 180424 02:55:53 mysqld_safe A mysqld process already exists 180424 02:55:55 mysqld_safe Logging to '/var/log/mysqld.log'. 180424 02:55:55 mysqld_safe A mysqld process already exists 180424 02:55:57 mysqld_safe Logging to '/var/log/mysqld.log'. 180424 02:55:57 mysqld_safe A mysqld process already exists 180424 02:55:59 mysqld_safe Logging to '/var/log/mysqld.log'. 180424 02:55:59 mysqld_safe A mysqld process already exists
怎么办?大佬们,在线等,谢谢。

