Default installs mainly puts GRUB into the MBR or to the specific root partition.

Is it possible just to install grub (no image whatsoever) into a USB thumbdrive (small size that is basically now useless) so that the grub menu will comes up when booting the computer with the USB inserted.

This means that booting without the USB inserted will result in booting up the default OS.

Any idea how can that be done?

lets start with the bios

Not all allow usb devices as a boot device so you may have to flash yours or check that your motherboard allows it

2) without usb inserted default os starts means you are using some other mbr and bootloader...eg hard drive or cd

3) no image what so ever? I do not know what you mean? Do you mean no os on usb?

a) there are a number of distros that now install onto usb
Mandriva is one of them they will sell you a stick

others you tend to d/l as a live cd and install as a separate option

b) if you truly want no os on usb ....and you want usb grub menu that means you need grub in usb mbr and you need a /boot partition that has the grub booting files

such a thing is certainly possible. But I am not sure what it achieves when grub in hard drive mbr is going to be faster.

check out my signature if you are interested.

Hello aus9

My mistake, should be explained it a little bit in detail.

Current situation,
I had a laptop that comes with a default OS (hda1) and later installed Debian on a separate partition (hda2).

As my current clients had voice out their wishes to see only the default OS on our laptops when working with them (not negotiable). I had reinstalled the default OS overriding the MBR.

The intent is to boot normally into the default OS when with these clients.



I've a spare 64M usb thumb drive and is looking into the possibility to just install grub onto it. I do not want to install an entire distro into it since I already had Debian in hda2

The intent is to insert USB thumb drive and boot into grub and select from menu what I really like to boot when NOT with these clients


Oops, I've yet to look into the links that you've provide

I think you might be better off just booting a distro from a Live CD/DVD or booting from a USB drive. As Aus stated, many distros can do this now.

Let us know if this works out. I'm curious.

Brandon

there is a secret way that can be done on the hard drive

edit your grub on laptop hard drive so the menu is in a certain order..ignoring the bits in each section I want

default 0

title hda1 (whatever it is) (something written on this line)
blah blah
blah blah

title
blah blah
blah blah

The key is the last title is completely blank...you will love it.

The trick is, only you know it exists, so MS users, will see only one line on the menu and will just wait for the timeout or press enter

So for you to get to second (blank) line just hit the down arrow and press enter and you are in.

Understand your method, in fact I can give it a timeout of 1 sec to shorten the screen from being seen

However, the real problem now is the MBR is already wiped out by the ms install so I need to get grub back into it again, hopefully into a USB thumb drive

Isn't it possible to use the NTLDR (MS bootloader) to boot Linux? I've heard of this, never tried it though as I don't use Windows anymore.

This would eliminate Grub entirely. You could rename Linux (*gasp*) to look like Windows.

Regards,

Brandon

no just re-install grub to mbr.

use a live cd or a linux install cd that has a recovery mode...go into console

either way once in a console or terminal run
but the root command may be wrong because you have yet to give us your partitions.
read my signature if you do not want to give that info.

but the simple rule is you reduce the number after the comma by one