新开通的cento7.5云主机，登录后按照如下步骤进行操作即可
yum -y upgrade
yum -y install fwupdate-efi
yum groupinstall "GNOME Desktop" "Graphical Administration Tools" "Xfce"
安装完成后，将系统启动模式设置为桌面模式：
systemctl set-default graphical.target
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yum install -y xterm
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wget https://www.realvnc.com/download/file/vnc.files/VNC-Server-6.6.0-Linux-x64.rpm && rpm -ivh VNC-Server-6.6.0-Linux-x64.rpm && vnclicense -add VKUPN-MTHHC-UDHGS-UWD76-6N36A && systemctl start vncserver-x11-serviced.service && systemctl enable vncserver-x11-serviced.service
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重启服务器：reboot
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关闭firewall：
#停止firewall
systemctl stop firewalld.service
#禁止firewall开机启动
systemctl disable firewalld.service