# 进入系统根目录
cd

# 下载mysql5.7
sudo wget http://repo.mysql.com/mysql57-community-release-el7-11.noarch.rpm 
sudo rpm -ivh mysql57-community-release-el7-11.noarch.rpm
# 清除yum缓存
sudo yum clean all
# 建立缓存
sudo yum makecache
# 安装
sudo yum install mysql-server
# 启动
sudo /bin/systemctl start mysqld.service
# 查询密码
sudo grep 'temporary password' /var/log/mysqld.log
# 返回密码 “,u5gwe0jpc%E”
2019-07-12T07:43:16.323336Z 1 [Note] A temporary password is generated for root@localhost: ,u5gwe0jpc%E

# 进入mysql
mysql -u root -p 
# 输入密码：
,u5gwe0jpc%E

# 修改密码，需要包含大小写字母、数字和特殊字符
ALTER USER 'root'@'localhost' IDENTIFIED BY 'Abc_00000000';
# 退出mysql
exit

# MySQL安装完成后，进行相关配置
# 安装成功后，将其加入开机启动
sudo systemctl enable mysqld

# 启动mysql服务进程
sudo systemctl start mysqld

# 配置mysql（设置密码等）
sudo mysql_secure_installation
Set 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] y       [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]


# 开放3306端口，使其它客户机也可以访问MySQL服务
# CentOS7默认使用的是firewall作为防火墙，我这里改为习惯常用的iptables防火墙

# 关闭防火墙 
sudo systemctl stop firewalld.service 
sudo systemctl disable firewalld.service 
sudo systemctl mask firewalld.service

# 安装iptables防火墙 
sudo yum install -y iptables-services

# 启动设置防火墙 
sudo systemctl enable iptables 
sudo systemctl start iptables

# 查看防火墙状态 
sudo systemctl status iptables

# 增加3306端口 
sudo vim /etc/sysconfig/iptables

# 增加： 按键 “i”插入 
-A INPUT -m state –state NEW -m tcp -p tcp –dport 3306 -j ACCEPT

# 按Esc,输入“：qw”,即可保存退出 

# 重启防火墙使配置生效 
sudo systemctl restart iptables.service