How to autologin (without entering username and password)(in text mode)
To boot into text mode
sudo vim /etc/default/grub
and change the following line:
GRUB_CMDLINE_LINUX_DEFAULT="text"
exit and enter:
sudo update-grub
Automatically login in text mode without specifying userid or password
Upstart Versions of Ubuntu
Add -a <your-user-name> to the line:
exec /sbin/getty -8 38400 tty1
in file /etc/init/tty1.conf
like so:
exec /sbin/getty -8 38400 tty6 -a gruber
/etc/init/tty1.conf is the upstart job that runs at the appropriate time to start the terminal session on tty1. Adding the -a option tells getty to call the login program with the -f option to sign that user in, bypassing the user prompt from getty and the password prompt from login.
Upstart is the Ubuntu system that operates as the kernel init process (process 1).
I tested this on my tty6 and it worked great. Because of the upstart respawn line if you exit the shell it will start back up again automatically.
Systemd Versions of Ubuntu
Newer versions of Ubuntu use mostly systemd to manage system processes. Therefore there are new ways of doing things.
systemd tty usage is also a little different with graphics terminals possibly running on the first few virtual terminals. tty6 is reserved to be a text virtual terminal with systemd and there will probably be others as well.
To have tty6 come up signed on as you enter:
sudo systemctl edit getty@tty6
A nano editor will come up in a temporary file. Enter the following into that editor:
[Service]
ExecStart=
ExecStart=-/sbin/agetty -o '-p -f gruber' -a gruber --noclear %I $TERM
Exit the editor.
Putting in the extra ExecStart= line is not a typo. it's very important as it tells systemd to forget about the original ExecStart parameter it already knows about (from /lib/systemd/system/[email protected]) so you can replace ExecStart.
You can check the results with the following command:
systemd-analyze verify [email protected]
I see some warnings there when I try this, but not about what we are doing here.
If there is already a tty process going on tty6 you'll have to restart it to see the results.
To figure this out I referred to the excellent answer at https://askubuntu.com/a/659268/63886. There Muru happened to use the same goal as an example on how to tailor systemd. His ExecStart line is:
ExecStart=-/sbin/agetty -a muru --noclear %I $TERM
The difference appears to be a couple more systemd related environmental variables appear in my version.
The end result of the above edit is the creation of a file called override.conf in /etc/systemd/system/[email protected]/ containing just what you typed above. If you were to create such a file yourself you would need to run the systemctl daemon-reload command to get systemd to recognize it, and again then possibly restarting any existing agetty process on that virtual console. systemctl --edit takes care of the daemon-reload for you.
open terminal and do as
sudo kate /etc/default/grub
then find this line and change as shown below
GRUB_CMDLINE_LINUX_DEFAULT="text"
now close the editor and do as
sudo update-grub
and do restart now