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Boot ISO off USB: commercial version

It seems the Isostick is getting a lot of press lately. They must’ve put out a PSA?

But I don’t get it.

Why pay a couple hundred bucks for a USB memory stick and software when you can get the memory for a couple of tens and the software for free? See multiple boot from ISO on USB pen drive below, for instance.

Most modern machines will boot off USB memory devices as if they were hard drives. That means a boot sector and partition table. The key to any boot is loading a BIOS extension that will be able to then load drivers that can read the bootable file system. The BIOS can load code from hard drives or floppies so the boot process starts with a ‘get me 512 bytes using these interrupts and disk access commands.’ See Further adventures in EFI booting for a rundown on the shell game being played at boot. Intel has the gory details at its Bootable CD-ROM Format Specification.

This ancient backwards compatibility is changing, of course, The BIOS memory constraints, both in terms of address space as well as hardware costs, have largely gone. Memory speed has improved too. Newer specifications have been developed and the result gets to be close to a firmware operating system that will handle not only the basic IO of all common modern devices on the mobo but also even run some applications for web browsing or multi-media purposes.

So what’s the big deal? Grub will load the BIOS extension to allow booting off an ISO image that resides on a USB memory stick. What does Isostick offer for its money? The news reports don’t seem to even realize that any other option exists for comparison and contrast. That is just poor reporting, I think.

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