How to change the default run level in RHEL7?

In earlier version of RHEL, we used to change the runlevels in /etc/inittab file.

But inittab is no longer used when using systemd. systemd uses ‘targets’ instead of runlevels.

By default there are 2 main targets

graphical.target à Runlevel 5 having GUI

 multi-user.targetàRunlevel 3 text based

To view current default runlevel/target

# systemctl get-default

To set a different target

#systemctl set-default TARGET.target

Ex: systemctl set-default graphical.target

Verification:

# systemctl get-default

graphical.target

Now reboot the machine to check whether the machine is booting up into graphical mode.

Alternate method to change the runlevel

You may be noticed the similar output when the systemctl set-default multi-user.target command is issued. What the command done is nothing but making a symbolic link of runlevel targets to the default target file.

rm '/etc/systemd/system/default.target'

ln -s '/usr/lib/systemd/system/multi-user.target' '/etc/systemd/system/default.target'

Check the current level.

# systemctl get-default

multi-user.target

Before making the symbolic link, let’s list out the files in the systemd directory.

# ls /lib/systemd/system/runlevel*target -l

lrwxrwxrwx. 1 root root 15 Aug  3 13:44 /lib/systemd/system/runlevel0.target -> poweroff.target

lrwxrwxrwx. 1 root root 13 Aug  3 13:44 /lib/systemd/system/runlevel1.target -> rescue.target

lrwxrwxrwx. 1 root root 17 Aug  3 13:44 /lib/systemd/system/runlevel2.target -> multi-user.target

lrwxrwxrwx. 1 root root 17 Aug  3 13:44 /lib/systemd/system/runlevel3.target -> multi-user.target

lrwxrwxrwx. 1 root root 17 Aug  3 13:44 /lib/systemd/system/runlevel4.target -> multi-user.target

lrwxrwxrwx. 1 root root 16 Aug  3 13:44 /lib/systemd/system/runlevel5.target -> graphical.target

lrwxrwxrwx. 1 root root 13 Aug  3 13:44 /lib/systemd/system/runlevel6.target -> reboot.target

As per the previous step, current default run level 3. 

Issue the following command to make a symbolic link of runlevel5.target to default.target file.

# ln -sf /lib/systemd/system/runlevel5.target /etc/systemd/system/default.target

or

# ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target

Again check the current level.

# systemctl get-default

runlevel5.target

Now the default runlevel is 5 (graphical mode), reboot the server and check it out.

# reboot