fedora16 更改默认登录的界面

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 -s /lib/systemd/system/<target name>.target /etc/systemd/system/default.target

and,
[root@virhuiai system]# pwd
/lib/systemd/system
[root@virhuiai system]# ls runlevel5.target -l
lrwxrwxrwx. 1 root root 16 Nov  3 10:29 runlevel5.target -> graphical.target
[root@virhuiai system]# ls runlevel4.target -l
lrwxrwxrwx. 1 root root 17 Nov  3 10:29 runlevel4.target -> multi-user.target
[root@virhuiai system]# ls runlevel3.target -l
lrwxrwxrwx. 1 root root 17 Nov  3 10:29 runlevel3.target -> multi-user.target
[root@virhuiai system]# ls runlevel2.target -l
lrwxrwxrwx. 1 root root 17 Nov  3 10:29 runlevel2.target -> multi-user.target
[root@virhuiai system]# ls runlevel1.target -l
lrwxrwxrwx. 1 root root 13 Nov  3 10:29 runlevel1.target -> rescue.target
[root@virhuiai system]# ls runlevel0.target -l
lrwxrwxrwx. 1 root root 15 Nov  3 10:29 runlevel0.target -> poweroff.target

in my system

[root@WLQ system]# ls /etc/systemd/system/default.target -l
lrwxrwxrwx. 1 root root 36 Nov 24  2011 /etc/systemd/system/default.target -> /lib/systemd/system/runlevel5.target
[root@WLQ system]# ls /lib/systemd/system/runlevel5.target -l
lrwxrwxrwx. 1 root root 16 Nov  3 10:29 /lib/systemd/system/runlevel5.target -> graphical.target

all targets in /lib/systemd/system/:
anaconda.target      mail-transfer-agent.target  runlevel4.target
basic.target         multi-user.target           runlevel5.target
bluetooth.target     network.target              runlevel6.target
cryptsetup.target    nss-lookup.target           shutdown.target
ctrl-alt-del.target  poweroff.target             sigpwr.target
default.target       printer.target              smartcard.target
emergency.target     reboot.target               sockets.target
final.target         remote-fs.target            sound.target
getty.target         rescue.target               swap.target
graphical.target     rpcbind.target              sysinit.target
halt.target          runlevel0.target            syslog.target
http-daemon.target   runlevel1.target            time-sync.target
kexec.target         runlevel2.target            umount.target
local-fs.target      runlevel3.target