Using usb-modboot as rescue-system on existing UEFI systems (usb-modboot v0.9)
de-ramon opened this issue · 2 comments
Hi,
in order to boot grml or other live-systems supported by usb-modboot directly from harddisk based UEFI-installations I tried to install usb-modboot into the ESP.
Win10 Installation
sda 8:0 0 100G 0 disk
├─sda1 8:1 0 9.8G 0 part /boot/efi # ESP
├─sda2 8:2 0 16M 0 part # MSR
├─sda3 8:3 0 89.7G 0 part #3 Win10
└─sda4 8:4 0 500M 0 part # Recovery
The 10 GB ESP hold usb-modboot:
root@grml / # tree -d /boot/efi/EFI
/boot/efi/EFI
├── Boot
│ ├── icons
│ ├── icons-backup
│ └── keys
├── Microsoft
│ ├── Boot
.....
│ └── Recovery
├── refind
│ ├── icons
│ ├── icons-backup
│ └── keys
├── tools
│ └── efifs
└── usb-modboot
I copied the stuff normaly resideing in usb-modboot-device/efi into /boot/efi/EFI/usb-modboot (sda1/EFI/usb-modboot).
Using rEFInd I can boot the EFI-Stuff shipped with the usb-modboot-modules, e.g. memtest.efi successfully.
Even the EFI/usb-modboot/loader.efi starts, but if I select "Continue to boot menu" nothing happens..
Invoking EFI/usb-modboot/grub.efi shows:
Starting grub.efi
Using load options ' '
Welcome to GRUB!
error: unknown filesystem.
error: disk 'core' not found.
Entering rescue mode....
grub rescue>
Any hints?
I uses VirtualBox for the tests. In order to get rEFInd running, you have to "patch" a little bit:
https://bbs.archlinux.org/viewtopic.php?pid=1231228#p1231228
cu,
ramon
You will probably need to rebuild grub.efi and make sure part_gpt is compiled into core.img instead of as a module. Maybe you need others too.
https://github.com/schierlm/usb-modboot/blob/master/build-grub#L37
Hi Michael,
thank you so much :)
It work's and it's cool :)
Here my mini HowTo:
Generate GPT capable grub.efi
Boot UEFI system with linux (here: grml64-full_2017.05.iso, because only Win10 is installed)
mkdir /boot/efi
mount /dev/sda1 /boot/efi
cd /root # no need to save build-files on hd! Live-System /root is ok
git clone https://github.com/schierlm/usb-modboot.git
cd /root/usb-modboot
vim build-grub +37 # edit line 37 as mentioned above to include part-gpt
old and new line 37:
...
# ./grub-mkimage -d ./grub-core -O x86_64-efi -o ../../../dist/usb-modboot/efi/boot/grub.efi -p '' -c ../confscript_efi fat part_msdos loopback
./grub-mkimage -d ./grub-core -O x86_64-efi -o ../../../dist/usb-modboot/efi/boot/grub.efi -p '' -c ../confscript_efi fat part_msdos part_gpt loopback
...
Build new grub.efi
apt update
apt install build-essential unzip gettext libfreetype6-dev dosfstools autoconf automake bison flex xfonts-unifont python ca-certificates git
./build-grub
./build-main
Install usb-modboot to ESP
mkdir /boot/efi/usb-modboot # holds usb-modboot-files as normal
mkdir /boot/efi/EFI/usb-modboot # just holds efi-loader
cp /root/usb-modboot/dist/usb-modboot/efi/boot/grub.efi /boot/efi/EFI/usb-modboot/grub-gpt_x64.efi
cp /root/usb-modboot/dist/usb-modboot/usb-modboot/* /boot/efi/usb-modboot
Put ISO in usb-modboot-folder
cd /boot/efi/usb-modboot
wget http://download.grml.org/grml64-full_2017.05.iso
wget http://download.grml.org/grml64-full_2017.05.iso.sha1
sha1sum -c grml64-full_2017.05.iso.sha1
If rEFInd is installed, just reboot:
cu,
ramon