Run Level 변경

1. 현재 설정된 runlevel 확인

[root@localhost ~]# runlevel 
N 3

2. inittab 에서 직접 runlevel 변경하기

[root@localhost ~]# vim /etc/init

# inittab is only used by upstart for the default runlevel.
#
# ADDING OTHER CONFIGURATION HERE WILL HAVE NO EFFECT ON YOUR SYSTEM.
#
# System initialization is started by /etc/init/rcS.conf
#
# Individual runlevels are started by /etc/init/rc.conf
#
# Ctrl-Alt-Delete is handled by /etc/init/control-alt-delete.conf
#
# Terminal gettys are handled by /etc/init/tty.conf and /etc/init/serial.conf,
# with configuration in /etc/sysconfig/init.
#
# For information on how to write upstart event handlers, or how
# upstart works, see init(5), init(8), and initctl(8).
#
# Default runlevel. The runlevels used are:
#   0 - halt (Do NOT set initdefault to this)
#   1 - Single user mode
#   2 - Multiuser, without NFS (The same as 3, if you do not have networking)
#   3 - Full multiuser mode
#   4 - unused
#   5 - X11
#   6 - reboot (Do NOT set initdefault to this)
# 
id:5:initdefault:

3. System reboot

[root@localhost ~]# reboot

1. RHEL7 에서 사용할 수 있는 target 정보 출력

[root@localhost etc]# systemctl list-units --type=target --all
UNIT                   LOAD   ACTIVE   SUB    DESCRIPTION
basic.target           loaded active   active Basic System
cryptsetup.target      loaded active   active Encrypted Volumes
emergency.target       loaded inactive dead   Emergency Mode
final.target           loaded inactive dead   Final Step
getty.target           loaded active   active Login Prompts
graphical.target       loaded active   active Graphical Interface
local-fs-pre.target    loaded active   active Local File Systems (Pre)
local-fs.target        loaded active   active Local File Systems
multi-user.target      loaded active   active Multi-User System
network-online.target  loaded inactive dead   Network is Online
network.target         loaded active   active Network
nfs.target             loaded active   active Network File System Server
nss-lookup.target      loaded inactive dead   Host and Network Name Lookups
nss-user-lookup.target loaded inactive dead   User and Group Name Lookups
paths.target           loaded active   active Paths
remote-fs-pre.target   loaded inactive dead   Remote File Systems (Pre)
remote-fs.target       loaded active   active Remote File Systems
rescue.target          loaded inactive dead   Rescue Mode
shutdown.target        loaded inactive dead   Shutdown
slices.target          loaded active   active Slices
sockets.target         loaded active   active Sockets
swap.target            loaded active   active Swap
sysinit.target         loaded active   active System Initialization
syslog.target          not-found inactive dead   syslog.target
time-sync.target       loaded inactive dead   System Time Synchronized
timers.target          loaded active   active Timers
umount.target          loaded inactive dead   Unmount All Filesystems

LOAD   = Reflects whether the unit definition was properly loaded.
ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
SUB    = The low-level unit activation state, values depend on unit type.

27 loaded units listed.
To show all installed unit files use 'systemctl list-unit-files'.

2. 현재 설정된 runlevel 확인

[root@localhost ~]# runlevel 
N 3

3. runlevel 변경

[root@localhost ~]# systemctl set-default graphical.target
rm '/etc/systemd/system/default.target'
ln -s '/usr/lib/systemd/system/graphical.target' '/etc/systemd/system/default.target'

4. runlevel 확인

[root@localhost ~]# runlevel 
N 5