On 03/09/2013 19:05, Grant Edwards wrote: > On 2013-01-07, Walter Dnes <waltd...@waltdnes.org> wrote: > >> For those of you who don't want to do the tap-dance listed at... >> http://www.gentoo.org/doc/en/liveusb.xml >> >> * My netbook's harddrive is normally /dev/sda, except when I boot from a >> USB stick. The stick will become /dev/sda and the harddrive becomes >> /dev/sdb >> >> * My desktop's harddrive is also /dev/sda. I took the linux minimal >> install ISO, ran isohybrid on it, with the command... >> >> isohybrid install-x86-minimal-20121213.iso >> >> If you don't have isohybrid... >> >> emerge sys-boot/syslinux >> >> * I then copied it over to a USB stick (/dev/sdb) with the command... >> >> dd bs=4M if=install-x86-minimal-20121213.iso of=/dev/sdb > > I did a 64-bit install from USB flash-drive a few days ago using the > older tap-dance, and it worked fine -- except I discovered one of my > "must have" apps is 32-bit only and didn't work correctly when run in > 32-bit emulation mode (I don't know why). > > So I tried Walter's recipe yesterday to do a 32-bit install. > > After running the isohybrid command, I compared the resulting image > with the original. They were identical. I copied the image to a USB > flash drive, and it booted just fine. > > It seems that the minimal install .iso images are already built for > hybrid booting from either CD or a generic block device (e.g. USB > mass-storage device). > > So what's the deal with http://wiki.gentoo.org/wiki/LiveUSB/HOWTO? > > Why isn't it just the steps below? > > 1) Copy the minimal install .iso to USB mass storage device. > > 2) Boot from USB mass storage device.
Copying an .iso to a USB stick does not give you a bootable USB stick. It gives you a USB stick with one large file, without bootloader, and the BIOS code can't make sense of it. USB mass storage devices are not CDs, you can't just dd an ISO9660 image to a USB stick and expect it to work (although files named *.img will often work doing exactly this) This is why unetbootin takes so long to do it's thing, it has to unpack image files and write them file by file to the USB stick -- Alan McKinnon alan.mckin...@gmail.com
