Change the Startup interface (http://comments.gmane.org/gmane.linux.redhat.fedora.general/442899)
If you want to switch the Display Manager, say from GDM to KDM.
Systemctl Disable Gdm.service
Systemctl Enable Kdm.service
or systemctl enable KDM--force
Reboot
First, set GNOME or KDE as the default startup desktop environment
Method 1: Modify the/etc/sysconfig/desktop to change the content after "desktop" to KDE or gnome as needed.
Method 2: Create the ". Xinitrc" file in the current user directory (note that there is a dot before the file name, which represents a hidden file), and the contents of the file are Startkde or gnome-session, choosing KDE or GNOME according to your needs.
Second, GNOME and KDE switching ("#" followed by the input command)
1. If you need to switch to GNOME:
#switchdesk Gnome
2. If you need to switch to KDE:
#switchdesk KDE
Linux Gnome KDE drip