Arch Linux

LoneStar

Member

Registered: 2009-12-06

Posts: 6

Backup USB boot disk

I've been googling for a while but can't seem to find an answer.

I have a hard disk with 3 partitions boot, root, and swap (using dm-crypt for all but boot, although that doesnt have much to do with the question).

Everything works great, but now I need to boot into this system using a USB drive. I can do this by creating a boot partition on the USB drive but for external reasons that isn't an option. I need ONLY the MBR (or very close to it) on the USB drive. Simply copying the MBR won't work either because you can't (to my knowledge) point to a partition on a different disk in an MBR partition table.

This is ultimately what I'm looking for:

USB DRIVE
----------------------------------
|MBR |   Fat32 FS                |
-----|----------------------------
     |___
/dev/sda |
---------|-----------------------------
|MBR |/boot | /                 | swap  |
-----------------------------------------

Is anything close to this possible?

Last edited by LoneStar (2014-01-27 02:11:47)

Algernop

Member

Registered: 2014-01-17

Posts: 30

Re: Backup USB boot disk

I have never attempted this myself, but perhaps installing grub (or w/e holds your fancy) on both MBR's and chainloading the /dev/sda grub from the thumbdrive grub would be worth looking into. Interesting problem though, will try looking into it during the weekend if problem persists.

Cheers!

edit: which would ofcourse violate the restraint of not installing a boot partiton, so never mind.

Last edited by Algernop (2014-02-03 11:21:07)