rpm -qa | grep mysql
rpm -qa | grep mariadb

remove mariadb-libs-5.5.52-1.el7.x86_64

yum install -y perl.x86_64
yum install -y libaio.x86_64
yum install -y net-tools.x86_64
yum install -y libtinfo*
yum install -y libncurses*

wget -P /tmp http://mirrors.ustc.edu.cn/mysql-ftp/Downloads/MySQL-5.7/mysql-community-common-5.7.31-1.el7.x86_64.rpm
wget -P /tmp http://mirrors.ustc.edu.cn/mysql-ftp/Downloads/MySQL-5.7/mysql-community-libs-5.7.31-1.el7.x86_64.rpm
wget -P /tmp http://mirrors.ustc.edu.cn/mysql-ftp/Downloads/MySQL-5.7/mysql-community-client-5.7.31-1.el7.x86_64.rpm
wget -P /tmp http://mirrors.ustc.edu.cn/mysql-ftp/Downloads/MySQL-5.7/mysql-community-server-5.7.31-1.el7.x86_64.rpm

rpm -ivh mysql-community-common-5.7.31-1.el7.x86_64.rpm 
rpm -ivh mysql-community-libs-5.7.31-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-5.7.31-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-5.7.31-1.el7.x86_64.rpm

systemctl restart mysqld.service

systemctl status mysqld.service

grep 'temporary password' /var/log/mysqld.log

mysql -u root -p

mysql -u root -p

ALTER USER 'root'@'localhost' IDENTIFIED BY '~1QAZxsw2'

use mysql;
update user set Host = '%' where Host = 'localhost' and User='root';
flush privileges;

firewall-cmd --zone=public --add-port=3306/tcp --permanent

firewall-cmd --reload

systemctl status firewalld

firewall-cmd --query-port=6379/tcp