Re: Grub and my second hard disk

[Csaba Henk]

On Sun, 8 Dec 2002, Thierry Laronde wrote:

> On Sat, Dec 07, 2002 at 11:35:36PM +0100, Csaba Henk wrote:
> > reintstalled Grub on /dev/hdd [with 
> > root (hd1,7)  
> > setup (hd1) ], 
> > but when I wanted to boot from it, there was displayed only "GRUB" at the
> > bottom of my screen (no error message), and then the system got frozen. I

> >  So finally I solved my problem but this phenomenon is strange to me, I
> > think it can be called a bug.
> 
> No.
> If you boot _from_ this very disk (the second one i.e. slave on secondary
> IDE bus) this disk is for the BIOS the first one (booting disk is 0x80). 
> The BIOS loads the MBR of the slave on secondary IDE (GRUB's stage1) whom
> you instructed to load the remaining stuff from the "other" disk (hd1). 
> Hence GRUB tries to seek for its files on the "other" disk i.e. master on
> primary IDE (which has became 0x81).
> 
> So, indeed correct solution is to tell GRUB to load the files from this very
> disk, not mentionning explicitely what it is (new version of GRUB does that 
> by default now ; previous version, 0.91 included, enforced a specification 
> of the drive), or to tell it to load from "hd0", taking this as identical 
> to "booting disk" (that's why the second solution succeeded but this has 
> nothing to do with setting primary IDE master to none or auto, except that 
> disabling the first disk it was more simple to install GRUB on second disk 
> by telling it the root for its files where on "hd0" --- to achieve this 
> while leaving first disk, you would have to swap virtually for GRUB's sake 
> the two disks).
> 
> This is not a bug, this is a BIOS feature.

That's OK. Anyway, I humbly advise the Great Grub that he could take the
grace of warning poor earthborns that the first solution does not work
when booting from the device just installed :)

Thanks, 
Csaba Henk 
(address@hidden, not on the bug-grub list)