UEFI Bootable Flashdrive

Question

I have seen many people ask similar questions. I might not be picking up the subtle differences, but here goes. I am a PC Tech. I have made a Bootable flash drive with Grub4dos that allows me to boot several versions of acronis, hirens boot cd, parted magic and several other useful tools from iso files. I have been beating my head against the keyboard trying to find a way to do a similar thing in UEFI. I have even seen people say first use grub2 and the chainload grub4dos. How can I make my flash drive work. I would prefer a single drive that would work in Bios and UEFI, but if I have to have 2 drives that's fine too.

Answer 1

You certainly can not use GRUB 2 to chainload GRUB4DOS in EFI mode, since GRUB4DOS is a BIOS-mode boot loader, and the EFI version of GRUB 2 can't launch a BIOS-mode boot loader.

GRUB 2, though, does include the ability to access files in an ISO-9660 disk image, so in theory, you should be able to configure it to boot from a collection of .iso files. I've never tried it myself, though. A quick Google search turned up this forum thread that claims to describe how to do this in BIOS mode. Some details might differ in EFI mode, though.

Another way that might work is to use my rEFInd boot manager and its ISO-9660 driver. You can't read .iso files with rEFInd, though, so you'd need to create partitions on your disk and copy the .iso files' contents to those partitions, as in sudo dd if=sourcefile.iso of=/dev/sdd7, assuming the USB flash drive is /dev/sdd and you want to copy sourcefile.iso to its seventh partition. I can't promise that this will work, but there's a good chance it will. Even if it works, of course, it's more awkward than reading from .iso files, since the partitions will be rather inflexible. The advantage of this approach over the GRUB approach is that it will require less mucking about with configuration files, since rEFInd should auto-detect and run the EFI boot loaders on the partitions.