Revert to Classic Command Line Login

[testingresults]

There are occasions when I want to boot into Kali as quickly as possible to run a few simple tasks. So, rather than dealing with a Desktop Environment, I like the default to be simply command line and have the option to load gdm3 if needed. Here's how to do that:


QUICK METHOD

If you want a quick copy/paste method:

cp -n /etc/X11/default-display-manager{,.bkup}
echo > /etc/X11/default-display-manager
cp -n /etc/gdm3/daemon.conf{,.bkup}
sed -i 's/^.*AutomaticLoginEnable = .*/AutomaticLoginEnable = True/' /etc/gdm3/daemon.conf
sed -i 's/^.*AutomaticLogin = .*/AutomaticLogin = root/' /etc/gdm3/daemon.conf
ln -s /usr/sbin/gdm3 /usr/bin/startx   # Old school ;)

Thank you, g0tmi1k!


STEP-BY-STEP WALKTHROUGH WITH EXPLINATIONS

STEP 1: Remove our Default Display Manager.

Since we don't want any graphical defualt display, we're going to simply clear the file out completely.
First, open a terminal. Fom here, we will backup our default display manager before we clear it out:

cp /etc/X11/default-display-manager /etc/X11/default-display-manager.backup
echo "" > /etc/X11/default-display-manager

STEP 2: Set GDM3 to autologin.

Since we're forced to login to even use the command line, there is really no reason to have GDM3 prompt us to login -- in a situation where we boot up wanting the desktop environment. So, we can tell gdm3 to autologin (to an account of your choosing) when, and if, you decide to load it.

cp /etc/gdm3/daemon.conf /etc/gdm3/daemon.conf.backup
leafpad /etc/gdm3/daemon.conf

Now, under section "[daemon]" we want to change both AutomaticLoginEnable and AutomaticLogin lines

[daemon]
# Enabling automatic login
#  AutomaticLoginEnable = true
#  AutomaticLogin = user1

Should now look like:

[daemon]
# Enabling automatic login
  AutomaticLoginEnable = true
  AutomaticLogin = root

NOTES

Now, whenever you boot into Kali, you'll be prompted to login at the command line, rather than the gdm3 GUI. Once logged in, you can always startup your desktop environment by simply typing in

gdm3

(optional) STEP 3: Use the the classic 'startx' command to run GNOME.
Thanks to user wlan0 for the suggestion

Simply open a terminal and type the following:

ln -s /usr/sbin/gdm3 /usr/sbin/startx

Now, rather than using gdm3 to start gnome, you'd use 'startx'.