下载mysql的安装包
访问mysql网站或者直接打开下载链接选择需要的mysql版本下载，这里选择mysql 8.0.20，如图：

也可以直接使用下面的命令下载：

#下载mysql
wget https://cdn.mysql.com/archives/mysql-8.0/mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar

安装mysql

#查看系统发行版本号
cat /etc/redhat-release
CentOS Linux release 7.8.2003 (Core)

#解压安装包
tar -zxvf mysql-8.0.20-1.el7.x86_64.rpm-bundle.tar
#解压后文件如下
mysql-community-client-8.0.20-1.el7.x86_64.rpm
mysql-community-common-8.0.20-1.el7.x86_64.rpm
mysql-community-devel-8.0.20-1.el7.x86_64.rpm
mysql-community-embedded-compat-8.0.20-1.el7.x86_64.rpm
mysql-community-libs-8.0.20-1.el7.x86_64.rpm
mysql-community-libs-compat-8.0.20-1.el7.x86_64.rpm
mysql-community-server-8.0.20-1.el7.x86_64.rpm
mysql-community-test-8.0.20-1.el7.x86_64.rpm
#这里安装client、common、devel、libs、server即可

#使用rpm通过如下命令安装所需软件包
rpm -ivh mysql-community-common-8.0.20-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-8.0.20-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-8.0.20-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-8.0.20-1.el7.x86_64.rpm
rpm -ivh mysql-community-devel-8.0.20-1.el7.x86_64.rpm

初始化并启动mysql

#初始化数据库
mysqld --initialize
#设置mysql数据目录所有者
chown -R mysql:mysql /var/lib/mysql
#开启mysql服务
systemctl start mysqld

登录mysql并设置权限

#查看mysql初始登录密码
cat /var/log/mysqld.log | grep password
2021-03-01T07:22:44.370984Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: wMrb1f_iqkKz

#登录mysql
mysql -uroot -p

#修改密码
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '新密码';

#远程访问授权
create user 'root'@'%' identified with mysql_native_password by '密码';
grant all privileges on *.* to 'root'@'%' with grant option;
flush privileges;

可视化工具兼容
MySQL 8.0 和以前的版本加密规则不一样，而现在的可视化工具只支持旧的加密方式，具体原因点这里，使用如下命令修改加密规则：

ALTER USER 'root'@'localhost' IDENTIFIED BY '密码' PASSWORD EXPIRE NEVER;
flush privileges;