An in-depth analysis of CentOS 7.1's run levels and boot modes

In most linux distributions, there are usually 8 runlevels

Runlevel System State

0 Halt the system

1 Single user mode

2 Basic multi user mode

3 Multi user mode

5 Multi user mode with GUI

6 Reboot the system

S, s Single user mode

Can be viewed in the file /etc/inittab

[root@wode003 ~]# cat/etc/inittab

-bash: cat/etc/inittab: No such file or directory

[root@wode003 ~]# cat /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 /usr/lib/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 view current default target, run:

# systemctl get-default

## To set a default target, run:

# systemctl set-default TARGET.target

#// get-default

[root@wode003 ~]# systemctl get-default

graphical.target

// set-default

[root@wode003 ~]# 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'

[root@wode003 ~]# systemctl get-default

multi-user.target

[root@wode003 ~]

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