System Environment: Centos 7.6
database version: Server version: 8.0.17 MySQL
shut down the firewall and selinux
download dependencies: yum install -y net-tools
unloading system comes with the initial MariaDB
# yum -y the Remove MariaDB *
1, browser search MySQL
2, navigation Download
3, find the drop-down Community Edition
4, download a comparison of the whole package 
or direct download links I provide:
wget https://cdn.mysql.com//Downloads/MySQL-8.0/mysql-8.0.17-1.el7.x86_64.rpm-bundle. tar
5. After the download is complete, unzip the package and upload
6, the mounting order of mounting
. 1, MySQL RPM -ivh 8.0.17-1.el7.x86_64.rpm-Community-Common-
2, RPM-libs -ivh MySQL-Community-8.0.17-1.el7.x86_64.rpm
. 3, RPM -ivh MySQL-Community-Client-8.0.17-1.el7.x86_64.rpm
. 4, RPM--ivh MySQL-Community Server-8.0.17-1.el7.x86_64.rpm
7, open the password-free login settings file /etc/my.cnf 
8, save and reboot MySQL
9, landing