我已成功使用此link在我的mysql80-community-release-el7-1.noarch.rpm中安装Centos 7，我尝试使用以下link更改datadir。它工作正常，直到第2步，但在第3步，当我尝试使用sudo systemctl start mysqld启动mysql时，它给了我一个这样的错误：
Job for mysqld.service failed because the control process exited with error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.
我尝试了以下解决方案：
但它们似乎都不适合我。这就是我的/var/log/mysqld.log文件所说的内容：
2018-06-15T09:08:32.294452Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.11) initializing of server in progress as process 14593
2018-06-15T09:08:37.698910Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: 7Y8An3/,r?ww
2018-06-15T09:08:40.729296Z 0 [System] [MY-013170] [Server] /usr/sbin/mysqld (mysqld 8.0.11) initializing of server has completed
2018-06-15T09:08:43.257796Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.11) starting as process 14695
2018-06-15T09:08:43.896289Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2018-06-15T09:08:43.936018Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.11' socket: '/var/lib/mysql/mysql.sock' port: 3306 MySQL Community Server - GPL.
2018-06-15T09:21:15.039285Z 0 [Warning] [MY-011068] [Server] The syntax 'validate password plugin' is deprecated and will be removed in a future release. Please use validate_password component instead.
2018-06-15T09:21:16.575642Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.11) MySQL Community Server - GPL
我是新手。