系统环境：centos7.4一,查看是否安装有数据库：yum list installed | grep mysqld/mariadb二，安装centos7系统带有mysql5.6安装包的yum源RPM资源包：rpm -
系统环境：centos7.4
一,查看是否安装有数据库：
yum list installed | grep mysqld/mariadb
二，安装centos7系统带有mysql5.6安装包的yum源RPM资源包：
rpm -Uvh http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpmyum clean allyum repolist三，安装msyql5.6：
yum -y install mysql-community-server
四，启动服务：
systemctl start mysqldsystemctl enable mysqld五，重置密码：是具体情况而定(可以省略，无密码登陆)
#mysql_secure_installationSet root password? [Y/n] y [设置root用户密码]Remove anonymous users? [Y/n] y [删除匿名用户]Disallow root login remotely? [Y/n] n [禁止root远程登录]Remove test database and access to it? [Y/n] y [删除test数据库]Reload privilege tables now? [Y/n] y [刷新权限]六，查看mysql版本：
mysql -Vmysql Ver 14.14 Distrib 5.6.39, for Linux (x86_64) using EditLine wrapper七，验证：(无密码)
mysql -uroot -p 密码
八、设置密码和远程权限
数据库密码设置：#set password for 'root'@'localhost'=password('userpasswd');
九、配置防火墙
firewall-cmd --zone=public --add-port=3306/tcp --permanent
