How to disable/enable GUI on boot in Ubuntu 20.04 Focal Fossa Linux Desktop - LinuxConfig.org

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In the following article you will learn how to disable GUI on boot in Ubuntu 20.04 Focal Fossa Linux Desktop
This is a companion discussion topic for the original entry at https://linuxconfig.org/how-to-disable-enable-gui-on-boot-in-ubuntu-20-04-focal-fossa-linux-desktop
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hello I have installed cinnamon but at startup login user can choose between gnome (ubuntu) and cinnamon before login. How can i disable it so user can only login with cinnamon?

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I tried to disable as described, and thought/hoped I would end up in a terminal of some kind, but my machine stops booting with the following message:

/dev/sda1: clean, …files…blocks
[FAILED] failed to start Load AppArmor profiles

and I can’t continue
Though I can ssh into the machine, but AppArmor fixes when searching aren’t plenty and they didn’t work so far.
‘sudo apt install apparmor-easyprof-ubuntu’
says can’t locate such a package
Tried autoremove -purge and purge snapd, but didn’t help :frowning:
Any suggestions?

For now I have reverted to boot into the desktop, that works.

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Hi DocMinus,

Welcome to our forums.

This is a strange issue you describe. Do you see any clues apparmor is logging? You can query for them with something like:

$ sudo journalctl --unit=apparmor

And check the time when your machine was in multi-user mode.

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Thanks for the welcome and the quick reply.
Not sure if this helps, the latest portion of that logfile. Sounds like the mysql server is the/one issue?
I don’t really need the server, that come from a recent “play and test” session.

– Reboot –
okt 10 12:21:33 Dreadnought apparmor.systemd[369]: Restarting AppArmor
okt 10 12:21:33 Dreadnought apparmor.systemd[369]: Reloading AppArmor profiles
okt 10 12:21:33 Dreadnought apparmor.systemd[410]: AppArmor parser error for /etc/apparmor.d in /etc/apparmor.d/usr.sbin.mysqld at line 9: Could not open ‘abstractions/mysql’
okt 10 12:21:33 Dreadnought apparmor.systemd[449]: Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox
okt 10 12:21:33 Dreadnought apparmor.systemd[456]: Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd
okt 10 12:21:33 Dreadnought apparmor.systemd[517]: Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox
okt 10 12:21:33 Dreadnought apparmor.systemd[535]: Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd
okt 10 12:21:33 Dreadnought apparmor.systemd[534]: AppArmor parser error for /etc/apparmor.d/usr.sbin.mysqld in /etc/apparmor.d/usr.sbin.mysqld at line 9: Could not open 'abstractions/mysq>
okt 10 12:21:33 Dreadnought apparmor.systemd[369]: Error: At least one profile failed to load
okt 10 12:21:33 Dreadnought apparmor.systemd[771]: Restarting AppArmor
okt 10 12:21:33 Dreadnought apparmor.systemd[771]: Reloading AppArmor profiles
okt 10 12:21:33 Dreadnought apparmor.systemd[785]: Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox
okt 10 12:21:33 Dreadnought apparmor.systemd[783]: AppArmor parser error for /etc/apparmor.d in /etc/apparmor.d/usr.sbin.mysqld at line 9: Could not open ‘abstractions/mysql’
okt 10 12:21:33 Dreadnought apparmor.systemd[792]: Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd
okt 10 12:21:33 Dreadnought apparmor.systemd[829]: Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox
okt 10 12:21:33 Dreadnought apparmor.systemd[870]: Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd
okt 10 12:21:33 Dreadnought apparmor.systemd[868]: AppArmor parser error for /etc/apparmor.d/usr.sbin.mysqld in /etc/apparmor.d/usr.sbin.mysqld at line 9: Could not open 'abstractions/mysq>
okt 10 12:21:33 Dreadnought apparmor.systemd[771]: Error: At least one profile failed to load
okt 10 12:21:23 Dreadnought systemd[1]: Starting Load AppArmor profiles…
okt 10 12:21:27 Dreadnought systemd[1]: apparmor.service: Main process exited, code=exited, status=1/FAILURE
okt 10 12:21:27 Dreadnought systemd[1]: apparmor.service: Failed with result ‘exit-code’.
okt 10 12:21:27 Dreadnought systemd[1]: Failed to start Load AppArmor profiles.
okt 10 12:21:30 Dreadnought systemd[1]: Starting Load AppArmor profiles…
okt 10 12:21:30 Dreadnought systemd[1]: apparmor.service: Main process exited, code=exited, status=1/FAILURE
okt 10 12:21:30 Dreadnought systemd[1]: apparmor.service: Failed with result ‘exit-code’.
okt 10 12:21:30 Dreadnought systemd[1]: Failed to start Load AppArmor profiles.

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After a complete removal of mysql the error message dissappears.
EDIT:
after some additional searches and checking I realized I didn’t have a shell activated, hence just a blinking cursor. Changed that in grub, now it’s all good.

1 Like
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I did this and set my home server to boot to multi user, now I can only access its terminal via ssh, the screen just shows a blinking cursor after turning on bluetooth.
Now to make matters worse, the server isn’t showing up on my router and I can no longer ssh to it. (This was caused by an issue unrelated to this guide…)
Can anyone help me out?
EDIT:
Fixed it by using the command:

systemctl enable getty@tty2

It forces the machine to use tty2 by default on boot.

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Thank you Lubos! I used the following:

sudo systemctl set-default multi-user
gnome-session-quit
sudo service gdm3 stop
sudo systemctl disable gdm3
sudo reboot