[root@dbserver ~]# more /etc/inittab
# inittab is no longer used when using systemd.
#
# ADDING CONFIGURATION HERE WILL HAVE NO EFFECT ON YOUR SYSTEM.
#
# Ctrl-Alt-Delete is handled by /etc/systemd/system/ctrl-alt-del.target
#
# systemd uses 'targets' instead of runlevels. By default, there are two main targets:
#
# multi-user.target: analogous to runlevel 3
# graphical.target: analogous to runlevel 5
#
# To set a default target, run:
#
# ln -sf /lib/systemd/system/<target name>.target /etc/systemd/system/default.target
#
查看當前的啓動運行模式
[root@dbserver ~]# systemctl get-default
graphical.target
設置默認啓動爲多用戶字符界面：
[root@dbserver ~]# systemctl set-default multi-user.target
rm '/etc/systemd/system/default.target'
ln -s '/usr/lib/systemd/system/multi-user.target' '/etc/systemd/system/default.target'
查看默認啓動的運行模式：
[root@dbserver ~]# systemctl get-default
multi-user.target 字符模式
[root@dbserver ~]#
設置默認啓動爲多用戶圖形界面：
[root@dbserver ~]# systemctl set-default graphical.target
rm '/etc/systemd/system/default.target'
ln -s '/usr/lib/systemd/system/graphical.target' '/etc/systemd/system/default.target'
[root@dbserver ~]#
查看默認啓動的運行模式：
[root@dbserver ~]# systemctl get-default
graphical.target 圖形模式
[root@dbserver ~]#
從字符界面切換到圖形界面：
方法1：執行#startx
方法2：執行#systemctl isolate graphical.target
總結：可以看到更改默認級別的操作即先刪除當前默認配置文件，然後再創建鏈接文件即可。