CentOS 6 이하 버전과 CentOS 7 버전의 run level 변경 방법

A. CentOS 6 이하 버전

/etc/inittab 의 ID 만 변경

B. CentOS 7

1. /etc/inittab 내용

[root@logserver ~]# 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

1. 현재 run level 확인

[root@logserver ~]# systemctl get-default

multi-user.target

2. run level 변경

run level 5로 변경

[root@logserver ~]# systemctl set-default graphical.target
Removed symlink /etc/systemd/system/default.target.
Created symlink from /etc/systemd/system/default.target to /usr/lib/systemd/system/graphical.target.

run level 3 으로 변경

[root@logserver ~]# systemctl set-default multi-user.target
Removed symlink /etc/systemd/system/default.target.
Created symlink from /etc/systemd/system/default.target to /usr/lib/systemd/system/multi-user.target.

3. 즉시 run level 변경

[root@logserver ~]# systemctl isolate multi-user.target