Migrating DVD ISO image to USB

[inode0]

On Tue, Dec 21, 2010 at 4:23 PM, Robert G. (Doc) Savage
<dsavage at peaknet.net> wrote:
> The Fedora-14-Live-multi.iso image is a DVD image that uses GRUB rather
> than isolinux to boot to a menu of Live CD ISO images. At 5.3 GB, it
> will not fit on an ordinary single layer DVD and requires a dual-layer
> DVD disc & drive. If it could be written to an 8GB USB thumb drive, it
> could be used to boot a system with a CD, an ordinary single-layer DVD,
> or no optical drive at all.
>
> The Fedora livecd-iso-to-disk utility cannot make a bootable USB from
> this image because it uses GRUB rather than isolinux like live CDs. I
> submitted a RFE to enhance l-i-t-d, but it was declined. I've tried
> using dd to copy the ISO image directly to the thumb drive:
>
>        # dd if=Fedora-14-Live-multi.iso of=/dev/sdd bs=2048
>
> but this does not produce a bootable device. Can anyone suggest a method
> that will work?

I think you can do this with a couple additional tweaks to grub after
copying everything from Fedora-14-Live-multi.iso to the usb stick.
Please be careful and double check the commands below.

Assuming the usb stick is mounted on $MNT and the grub configuration
is setup to use a CD we would need to change one line in grub.conf for
booting from USB instead.

# perl -p -i -e 's#root \(cd\)#root \(hd0,0\)#' $MNT/boot/grub/grub.conf

We also probably need to adjust the device.map for USB with something similar to

# echo '(hd0)	/dev/sda' > $MNT/boot/grub/device.map

You might need to do the above step from a machine where the usb stick
is mounted on /dev/sda1 ... I'd have to test that to be sure.

Finally run grub-install on the image with great care

# grub-install --root-directory=$MNT --no-floppy '(hd0)'

With some variation of these I think we can get it to boot from a usb
stick. Did I say be careful? :)

John