Hard drive install (upgrade) from USB drive?

[Les Mikesell]

Arch Willingham wrote:
> I have done it a bunch on six machines (its how I upgrade each time). I got this from this website (http://www.duncanbrown.org/linux/system_administration/fedora_core_grub_install/)and have used it with FC5, FC6 and FC7:
> 
> 1. Put the ISO on the USB device (because I have a terrible memory, I put it in the root but you can put it anywhere as long as you can remember the directory!).
> 2. Either grab the kernel image and initrd root image or open the ISO and extract vmlinuz and initrd.img.
> 3. rename vmlinuz to /boot/FC7-install
> 4. rename initrd.img to /boot/FC7-install.img
> 5. Add these three lines to your /boot/grub/grub.conf 
> 
> title Fedora Core 7 Installation
> 	kernel /FC7-install
> 	initrd /FC7-install.img
> 
> 6. Reboot your machine. As it boots you have the chance to this the space bar, do so and pick the menu item called  "Fedora Core 7 Installation"
> 7. It will go through the normal set of questions. Once it gets to asking you where you want to install from, pick hard drive and the pick the USB drive (on every install I have done, it is the very last dive listed at the bottom). The enter the directory in the bottom box (or just "/" if you put it in the root).
> 8. From there it will let you pick the rest of the options.

The above assumes that you already have linux booting from grub on the 
machine. I've been too lazy to try this myself, but I'd like to know if 
it will work using 2 USB devices - one small flash key type, one large 
enough to hold the iso/dvd images, perhaps for several different 
versions or distributions (the laptop drive based versions are available 
in sizes over 100gigs now and run from USB power).

1. loopback mount the iso and copy the diskboot.img from the /images 
directory to the small raw USB device to make it bootable.  (I think 
this step requires Linux.  Is there an equivalent if you had done the 
download under windows?)  This will wipe out anything else on the drive 
which is why you don't want to do it to the larger device.

2. plug both the small and large USB devices into a PC and boot.

Theoretically this should boot the installer from the small flash device 
and it should offer the partition(s) on the large one as source for a 
hard disk install.  This sounds easier and "greener" than burning CDs 
for every distro/version and still very fast and portable.

-- 
   Les Mikesell
    lesmikesell at gmail.com