Re: How Do I Get GRUB to See the External USB Drive?

On Mon, Jun 15, 2009 at 12:42 PM, Sjoerd Hardeman <
sjoerd@xxxxxxxxxxxxxxxxxxxxx> wrote:

Scarletdown schreef:
On Mon, 2009-06-15 at 16:53 +0200, Sjoerd Hardeman wrote:
Can you check the contents of /boot/grub/device.map? I think you need to
make sure your usb device is mentioned there for it to work at boot
time. If it is not there, redo update-grub and check if the usb drive is
added to device.map. If so, do a grub-install and then things should
work.

cat /boot/grub/device.map
(hd0) /dev/hda
(hd1) /dev/hdb
Try adding
(hd2) /dev/hd? (your usb disk)
and then do a grub-install


I have since gone on to plan B and installed XP on the internal SCSI drive
(/dev/sda1). This has created a whole new problem.

Before I installed, I went into the BIOS and disabled the IDE hard drive
(/hda), just so that Windows would not overwrite my MBR. Well, it overwrote
it anyway, apparently completely ignoring the BIOS settings. Now the Linux
side of the system is not bootable.

I booted with an Ubuntu 6.10 CD and tried to repait the MBR with a procedure
I found on the Ubuntu forums (went with the Ubuntu disk because that was the
first Live CD I was able to dig up.)

It went like this:

sudo grub
find /boot/grub/stage1 (this returned something to the effect of hd(0,0) )

Then I did root (hd0,0)
setup (hd0)
quit

I then rebooted without the Ubuntu disk in the drive, and the system still
went to Windows, even though the boot order in the BIOS is set to
CD-ROM/Floppy/HDD0 (where HDD0 is the IDE hard drive, not the SCSI drive).

I tried rebooting with the SCSI drive disconnected and the system just froze
up as if there was no bootable partition at all (I had double checked to
make sure the drive's partition was set active).

I tried installing GRUB on the MBR of the SCSI drive and setting root to the
first partition on the Linux drive, but that also failed (all that happened
was GRUB was printed across the screen endlessly.)

Any other suggestions to get my Linux system back and operational again?
Like I said, it is there, just not accessible. Is it possible that the
version of GRUB that is on the Ubuntu disk (I believe 6.10 is Feisty
Fawn...not sure what the most recent is)is too old for my sustem? (I seem
to recall updating it just a day or two ago. In fact, I definitely remember
updating GRUB just yesterday in hopes that would help with the original
problem.

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