1.安装开发环境依赖

yum groupinstall -y "Development Tools"

2.查看系统中是否存在mysql和mariadb，若有则删除

查找mysql
ps -ef|grep mysql
查找mariadb
ps -ef|grep mariadb

3.删除mariadb-libs

yum remove -y mariadb-libs

4.安装一些依赖

wget http://mirror.centos.org/centos-7/7.5.1804/os/x86_64/Packages/libaio-0.3.109-13.el7.x86_64.rpm
rpm -ivh libaio-0.3.109-13.el7.x86_64.rpm
yum -y install numactl
yum install -y net-tools

A—>安装mysql

rpm -ivh mysql-community-common-5.7.23-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-5.7.23-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-5.7.23-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-5.7.23-1.el7.x86_64.rpm

5.初始化mysql

mysqld --initialize --user=mysql

6.获取mysql初始化密码

cat /var/log/mysqld.log

7.启动mysql服务

systemctl start mysqld.service

或者

service mysqld start

或者使用mysql启动脚本

/etc/inint.d/mysqld start

8.登陆mysql修改用户密码

alter user 'root'@'localhost' identified by '123456';

9.放心端口

/sbin/iptables -I INPUT -p tcp --dport 3306 -j ACCEPT

10.设置外网可连

use mysql;
update user set host = '%' where user = 'root';