USB Boot, ISO images - is this possible?

[batfastad]

Hi everyone

I know it's possible to boot off USB drives without too much work, there's hundreds of tutorials I've found. Each slightly specific to the OS you're looking to boot.

But what I'm wondering is... is it possible to boot an ISO image from a USB stick?

Ideally you could set up a bootable USB stick, but when it boots it loads some sort of custom Linux boot menu which lists all the ISO images available on the USB drive.
Then you just select which one you want to boot.

Is that possible?

Cheers, B

[Agent]

Having a look about Google, there seems to be loads of people asking this but without a solution.

Thinking about it though, Knoppix can do something similar.

http://www.knoppix.net/wiki/USB_Based_FAQ
Booting to an Image on an Alternative Device

Poor Man's USB Based Boot (Boot from USB flash memory stick and then continue boot with Knoppix image stored on a harddisk or a CD or an external USB harddisk ) How To:

What you will need:

* Computer with BIOS capable of booting from USB keydrive (select USB-HDD). (Unfortunately, some buggy BIOS just wont boot from my USB stick, such as all versions up to F9 for the Gigabyte GA-8IEXP motherboard).
* USB keydrive that can boot as USB-HDD device. Make sure you read the product specification, only some USB flash sticks support this feature. (or see this 4/05 review on Ars Technica http://arstechnica.com/reviews/hardware/flash2005.ars . Only 3 of 10 reviewed sticks are bootable.)
* Linux with GRUB grub boot loader already installed. I just use Knoppix.
* Read Win Partition Poor Man Installation for the more versatile boot mechanism we gonna utilize here.

Steps: (Cautions: Unmount usb stick before you remove it from USB slot to avoid data loss. Backup the MBR of harddisk and USB stick, see the link above)

1. Insert the USB stick, use cfdisk to create a partition with boot flag on this device ( cfdisk /dev/sda ). Create a file system on the newly created partition.(eg. mke2fs -m0 /dev/sda1)
2. Mount the partition and install grub boot loader on this device ( mount /dev/sda1 /mnt/usb && grub-install --root-directory=/mnt/usb /dev/sda ). Now the USB stick is already bootable, you will enter the interactive GRUB shell enviroment if you boot with it.
3. Copy kernel and initrd to USB stick. To continue boot from an knoppix 3.6 ISO image stored on a NTFS/FAT harddisk partition, you will need the kernel and miniroot.gz files from Ruymbeke's files.
4. Create a file menu.lst under dir /mnt/usb/boot/grub, I just copied the one from Ruymbeke's files pasted in Win Partition PMI. Specify the location of the newly copied kernel and minirt files in this file, note (hd0,0) is the first partition on USB stick when you boot from it, and the first harddisk likes to be hd1. To find out how GRUB map devices, press key c when you see GRUB boot menu at boot time, then type root ( and press TAB key, see the GRUB texinfo for detail.

DONE.

I have created a 32M boot partition on a 128M USB flash stick, and use it to boot Knoppix ISO image stored in a FAT32 partition shared by Windows, or to boot ubuntu live CD (basemodule is Morphix) already copied to another partition. The purpose is to reduce the time to burn these Linux Live CDs and less CDs to carry with.

So by the looks of it you could probably do it with some modification. I don't see why another FAT32 based partition on the USB drive with the ISO image/s on it wouldn't work, but you'll have to wait for the real Linux people to tell you if it can be done, and how hard it may be
Speed may be an issue though - make sure you get yourself a fast drive.

I'm going to move this to software as it will get better replies there

[batfastad]

Ah ok, thanks for the suggestions.
I think it would be a mega-cool thing for someone to try and do.
I'd love to be able to have all my recovery ISO images (UBCD, UBCD4Win, Knoppix, PuppyLinux etc) all stored in a folder on my USB drive.

Hope someone can work it out!

Cheers, B

PS: Sorry for delayed reply, didn't have notification on

[directhex]

you can only do it using knoppix's method because it can boot a kernel, mount an iso, then jump from one kernel into another & carry on booting

windows can't be chain-loaded from linux

[Agent]

Isn't booting the Kernel directly from the drive a possibility? More so if its just emulating a HD?

How well can the Kernel manage with different machine configs? Is it possible to make one thats fairly minimal, but would work on almost any x86 based PC?