linux(centos) 7 设置运行模式

发现熟悉的/etc/inittab中没有了修改默认运行级别，打开inittab如下

[root@localhost init.d]# vi /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

中间没有了熟悉的 id:5:initdefault

修改方法为：
1.首先删除已经存在的符号链接
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rm /etc/systemd/system/default.target
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2.默认级别转换为3(文本模式)
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ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target
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或者默认级别转换为5(图形模式)
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ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target
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3.重启
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reboot
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如果保存了错误的运行的模式，开机时输入"e" ，选择第二行再输入e，再输入1【单用户运行级别】，因为可以不用去读取配置文件，再按b，进去再重新设置