Bootable grub USB stick (EFI and BIOS for Intel)
I'm using grub version 2.02~beta2-2.
I want to make a USB stick that's capable of booting Intel architecture EFI machines, both 64-bit (x86_64) and 32-bit (ia32). I'm starting from a USB stick which is attached to a running debian system as /dev/sdX. I have nothing that i care about on that USB stick, and all data on it will be destroyed by this process.
I'm also going to try to make it bootable for traditional Intel BIOS machines, since that seems handy.
I'm documenting what I did here, in case it's useful to other people.
Set up the USB stick's partition table:
parted /dev/sdX -- mktable gpt parted /dev/sdX -- mkpart biosgrub fat32 1MiB 4MiB parted /dev/sdX -- mkpart efi fat32 4MiB -1 parted /dev/sdX -- set 1 bios_grub on parted /dev/sdX -- set 2 esp onAfter this, my 1GiB USB stick looks like:
0 root@foo:~# parted /dev/sdX -- print Model: USB FLASH DRIVE (scsi) Disk /dev/sdX: 1032MB Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 1049kB 4194kB 3146kB fat32 biosgrub bios_grub 2 4194kB 1031MB 1027MB efi boot, esp 0 root@foo:~#make a filesystem and mount it temporarily at /mnt:
mkfs -t vfat -n GRUB /dev/sdX2 mount /dev/sdX2 /mntensure we have the binaries needed, and add three grub targets for the different platforms:
apt install grub-efi-ia32-bin grub-efi-amd64-bin grub-pc-bin grub2-common grub-install --removable --no-nvram --no-uefi-secure-boot \ --efi-directory=/mnt --boot-directory=/mnt \ --target=i386-efi grub-install --removable --no-nvram --no-uefi-secure-boot \ --efi-directory=/mnt --boot-directory=/mnt \ --target=x86_64-efi grub-install --removable --boot-directory=/mnt \ --target=i386-pc /dev/sdXAt this point, you should add anything else you want to /mnt here! For example:
- a kernel and initramfs from your own computer
- debian-installer ISOs
- firmware blobs for that annoying proprietary device
- BIOS updates
- debirf images
umount /mnt sync