Re: [gentoo-user] VFS: Cannot open root device "hda6" or unknown-block(3,6)

[Mick]

On Tuesday 26 December 2006 18:26, Bruce Burden wrote:
>    Hi Fei,
>
> On Tue, Dec 26, 2006 at 05:35:59PM +0800, fei huang wrote:
> > didn't you separate your boot partition from / ?
> >
> > -->   root (hd1,5)
> > this indicates your BOOT partition (/boot) is located at  /dev/hdb6
>
> 	Originally, this would have been:
>
> 	root(hd0,5)
>
> > -->   kernel /boot/linux-2.6.15-gentoo-r1 root=/dev/hda6
> > this indicates your ROOT partition ( your / ) locates at /dev/hda6, is is
> > possible?
>
> 	while I have not changed this line.
>
> 	/boot is part of the / heirarchy, which is on /dev/hda6 assuming
>     the disk is an IDE disk in the laptop.
>
> 	What I have is:
>
> IDE: FreeBSD, with FreeBSD MBR
> USB enclosure:
>      first 2 partitions Windows
>      hda5  - SWAP
>      hda6  - /
>      hda7  - /var
>      hda8  - /usr
>      hda9  - /tmp
>      hda10 - /usr/src
>      hda11 - /usr/portage
>      hda12 - /home
>      GRUB is instaled in MBR.
>
> 	Now, on boot, the FreeBSD bootloader gets me to the GRUB loader on
>    the USB drive.
>
> 	What I believe I need to know is how to remap the partitions on the
>    original IDE drive to SCSI partitions, because that drive is now in the
> USB enclosure.

You can use tab auto-completion in grub to see what drives and partitions are 
identified as.

> 	Also, I need to know how to "change" the Windows partition so that
>    Windows believe it is the first disk, otherwise it will not boot.

That's right, it won't.  You need the map command in your grub.conf:

map (hd0) (hd1)
map (hd1) (hd0)

WinXP will now think that it is on the first disk and it will boot happily.

-- 
Regards,
Mick