[root@cdhnode1 Desktop]# yum install lightdm -y[root@cdhnode1 Desktop]# vi /etc/lightdm/lightdm.conf修改内容如下：[XDMCPServer]enabled=trueport=177[SeatDefaults]user-session=/usr/bin/startxfce4greeter-session=lightdm-gtk-greetergreeter-hide-users=true[root@cdhnode1 Desktop]# systemctl disable gdmRemoved symlink /etc/systemd/system/display-manager.service.[root@cdhnode1 Desktop]# systemctl enable lightdm.service Created symlink from /etc/systemd/system/display-manager.service to /usr/lib/systemd/system/lightdm.service.[root@cdhnode1 Desktop]# systemctl start lightdm.service[root@cdhnode1 Desktop]# yum groupinstall xfce -y[root@cdhnode1 Desktop]# cd /usr/share/xsessions/ && lsgnome-classic.desktop  gnome-custom-session.desktop  gnome.desktop  xfce.desktop[root@cdhnode1 xsessions]# mkdir back && mv gnome* back && lsback  xfce.desktop[root@cdhnode1 xsessions]# init 3 && init 5PolicyKit daemon disconnected from the bus.We are no longer a registered authentication agent.PolicyKit daemon disconnected from the bus.We are no longer a registered authentication agent.PolicyKit daemon reconnected to bus.Attempting to re-register as an authentication agent.We are now a registered authentication agent.

参考教程：

1.http://www.linuxidc.com/Linux/2017-03/142011.htm

2.https://www.zybuluo.com/wuzhimang/note/392271