How do I enable autologin on TTY running on the Controllers serial port [Raspbian Buster/Bullseye/Bookworm]?

To enable auto logins on the TTY running on any serial port on the Controller log in and run the following commands changing "USERNAME" to your username and reboot.

sudo mkdir -p /etc/systemd/system/serial-getty@ttyS0.service.d/
sudo bash -c "cat > /etc/systemd/system/serial-getty@ttyS0.service.d/autologin.conf << EOF
[Service]
ExecStart=
ExecStart=-/sbin/agetty --autologin USERNAME --noclear %I \$TERM
EOF"

And to disable it run the following command and reboot.

sudo rm -rf /etc/systemd/system/serial-getty@ttyS0.service.d/

When enabling this all users with access to the Controller Pi serial port will be able to log in without any authentication.

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