borderos

README

BorderOS

Hardware supported

• EdgeRouter Lite (ERL-3)

Design

Based on Gokrazy, ideas from Router7.

Installation

EdgeRouter Lite

• Unplug the internal flash drive, or obtain a new one

• gok overwrite --full /dev/sdN

  • Using gok from the fork of gokrazy-tools

• Connect to the serial console of the EdgeRouter and power it on

• Before the OS loads press any key to drop into u-boot

• Update the bootcmd variable

  • You may wish to save the default first, e.g. setenv oldbootcmd $bootcmd

  setenv bootcmd fatload usb 0 $loadaddr vmlinuz; bootoctlinux $loadaddr coremask=0x3 root=/dev/sda2 rootwait init=/user/brd mtdparts=phys_mapped_flash:512k(boot0),512k(boot1),64k@1024k(eeprom)
  

• Store this: saveenv

• Reboot the router

Testing

The brd init program can be tested on a regular Linux system without needing the full gokrazy image.

Partition a system with with a disk layout as follows:

• 500MB EFI
• ext4 /
• ext4, unmounted, identically-sized to / partition
• ext4, unmounted, to be used as gokrazy /perm

This is the layout used by gokrazy.

Build cmd/brd and install it as /brd.

Create /config and add a config.cue with the system configuration.

Setup GRUB2 to boot using brd. On Debian this can be done by editing /etc/grub.d/40_custom and setting up a boot entry as follows:

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'BorderOS' {
	load_video
	insmod gzio
	insmod part_gpt
	insmod ext2
	echo	'Loading Linux 6.1.0-13-arm64 ...'
	linux	/boot/vmlinuz-6.1.0-13-arm64 root=/dev/nvme0n1p2 init=/brd
	echo	'Loading initial ramdisk ...'
	initrd	/boot/initrd.img-6.1.0-13-arm64
}

Replacing the kernel lines and root device to match your own system.

Then run sudo update-grub.