[root@odi12c ~]# yum groupinstall "Server with GUI"
[root@odi12c ~]# systemctl get-default
multi-user.target
[root@odi12c ~]# systemctl set-default graphical.target
Removed symlink /etc/systemd/system/default.target.
Created symlink from /etc/systemd/system/default.target to /usr/lib/systemd/system/graphical.target.
[root@odi12c ~]# systemctl get-default
graphical.target
[root@odi12c ~]# reboot