[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
#
fmc:2345:respawn:/opt/ibm/db2/V10.5/bin/db2fmcd #DB2 Fault Monitor Coordinator
[root@dbserver ~]# systemctl get-default
graphical.target
设置默认启动为多用户字符界面：
[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‘
查看默认启动的运行模式：
[root@dbserver ~]# systemctl get-default
multi-user.target 字符模式
[root@dbserver ~]#
设置默认启动为多用户图形界面：
[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 ~]#
查看默认启动的运行模式：
[root@dbserver ~]# systemctl get-default
graphical.target 图形模式
[root@dbserver ~]#
从字符界面切换到图形界面：
方法1：执行startx
方法2：执行systemctl isolate graphical.target
总结：可以看到更改默认级别的操作即先删除当前默认配置文件，然后再创建链接文件即可。
本文出自 “花之旭's Blog” 博客，请务必保留此出处http://huazhixu123.blog.51cto.com/1591874/1983662
原文：http://huazhixu123.blog.51cto.com/1591874/1983662