ParrotSecurity 4.2: GRUB2 and Linux with serial console

This article will describe changing GRUB2 and Linux to serial console. This is not for desktop environment but embedded system and virtual machine environment.

1 /etc/default/grub

Change /etc/default/grub as below.

  • Change GRUB terminal to console and ttyS0. This will provide one GRUB to a monitor display and serial console.
  • Change linux kernel console to tty1 and ttyS0. This setting will be taken over to userland, and there will be two login prompt for tty1 and ttyS0.
#!/bin/sh -e

sudo cp /etc/default/grub /etc/default/grub.orig
cat <<EOF | sudo tee /etc/default/grub
GRUB_DISTRIBUTOR=\`lsb_release -i -s 2> /dev/null || echo Debian\`
GRUB_CMDLINE_LINUX_DEFAULT="noautomount console=tty1 console=ttyS0,115200"
GRUB_TERMINAL="console serial"
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 \
--parity=no --stop=1"

sudo grub-mkconfig -o /boot/grub/grub.cfg
sudo reboot

2 Execution result

GRUB to monitor display is as below.


GRUB to serial console is as below. This article used "sudo virsh console <vmname>" for connecting serial console.


Login prompt to monitor display is as below. tty1 is displayed with press Ctrl + Alt + F1.


Login prompt to serial console is as below.