Don't have access to a 22.03 box at the moment, look in the /etc/inittab, check if there's a line
similar to ttyMSM0::askfirst:/usr/libexec/login.sh, and comment it out.
In the top (system) block of /etc/config/system, change ttylogin to 1 instead of 0. This will require a password on the serial port.
You can disable serial ports in the BIOS or unplug the hardware inside the case. GRUB may have a long delay if it remains configured to use serial but there are no ports on the bus.
Note that Linux was never intended to be very hard against someone who has physical access to the computer.
::sysinit:/etc/init.d/rcS S boot
::shutdown:/etc/init.d/rcS K shutdown
ttyS0::askfirst:/usr/libexec/login.sh
hvc0::askfirst:/usr/libexec/login.sh
#tty1::askfirst:/usr/libexec/login.sh
This worked. Login is disabled now. but kernel messages are still printing
Solved by removing serial commands & adding quiet in menuentry /boot/grub/grub.cfg
menuentry "OpenWrt" {
linux /boot/vmlinuz root=PARTUUID=e17df3c5-02 rootwait noinitrd quiet
}