一、下载

下载地址：https://dev.mysql.com/downloads/mysql/

二、解压

tar xvf mysql-5.7.39-1.el7.x86_64.rpm-bundle.tar

三、卸载已安装包

rpm -qa|grep mariadb
mariadb-libs-5.5.68-1.el7.x86_64

rpm -e --nodeps mariadb-libs-5.5.68-1.el7.x86_64

四、按顺序安装rpm包

rpm -ivh mysql-community-common-5.7.39-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-5.7.39-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-5.7.39-1.el7.x86_64.rpm
// 如果安装 mysql-community-server-5.7.39-1.el7 报 libaio.so.1 依赖错误，需先安装 libaio-0.3.109-13.el7.x86_64.rpm
rpm -ivh libaio-0.3.109-13.el7.x86_64.rpm
rpm -ivh mysql-community-server-5.7.39-1.el7.x86_64.rpm

安装 server 还可能报错：

rpm -ivh mysql-community-server-5.7.39-1.el7.x86_64.rpm 
warning: mysql-community-server-5.7.39-1.el7.x86_64.rpm: Header V4 RSA/SHA256 Signature, key ID 3a79bd29: NOKEY
error: Failed dependencies:
	net-tools is needed by mysql-community-server-5.7.39-1.el7.x86_64

执行以下命令安装 net-tools 解决：

yum install net-tools -y

五、启动

systemctl  start  mysqld

六、找到初始密码

cat /var/log/mysqld.log | grep 'password is generated'

七、修改密码并授权

alter user 'root'@'localhost' identified by 'xxxxxx';
grant all privileges on *.*  to  'root'@'%'  identified by 'xxxxxx'  with grant option;
flush privileges;

八、开启防火墙，允许外网访问

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