1.在线安装MYSQL

1.查看是否有安装过mysql

rpm -qa | grep -i mysql

2.删除mysql

yum -y remove MySQL-*

3．把所有出现的目录统统删除

find / -name mysql
rm -rf 目录

4．删除配置文件

rm -rf /etc/my.cnf

5.删除mysql的默认密码

rm -rf /root/.mysql_sercre（可能打错）

6.配置Mysql 8.0安装源

sudo rpm -Uvh https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm

7.安装Mysql 8.0

sudo yum --enablerepo=mysql80-community install mysql-community-server

8.启动mysql服务

sudo service mysqld start

9.查看mysql服务运行状态

service mysqld status

10.查看root临时密码

grep "A temporary password" /var/log/mysqld.log

11.登录以后修改密码

ALTER USER ‘root’@‘localhost’ IDENTIFIED BY ‘12345’;

12.退出后重启MYSQL

service mysqld stop;
service mysqld start;

13.修改远程访问

select user,authentication_string,host from user;
update user set host = '%' where user = 'root';
FLUSH PRIVILEGES;