Re: LILO config

[Joseph S D Yao <jsdy gwyn tux org>]

> hda is a Win95 drive - hda1 FAT16 1Gig, hda2 FAT32 1Gig
> hdc Other OSes - hdc1 - WinNT (900Meg), hdc2 Extended DOS FAT 16(512Meg),
> hdc3 Ext2(500Meg), hdc4 Linux swap(66Meg)
> (hdc contains the NT loader - must change boot priority)  

You are aware that BIOS restrictions make it necessary to contain a
bootable partition entirely below cylinder 1024, right?

> I had to perform the install on hdc as hda so I could use my selectbay
> cdrom.  After booting from floppy and installing LILO, stripping LILO using
> "dd" I was able to boot Linux using the NT loader.  Pretty painless
> actually.  The last thing I did was change /etc/fstab to use hdc3 because
> this would be its final location.  I then moved the drive back to the
> selectbay (hdc).  (I also did this so the NT loader would not install on
> hda.)
> 
> I am now able to boot from floppy w/ root=/dev/hdc3 and Linux runs. 
> However after modifying /etc/lilo.conf to use hdc3, lilo complains that it
> is not on the 1st drive.  I installed it anyhow and stripped it with "dd". 
> I can now load LILO from the NT loader on hdc but LILO hangs with "LI".
> 
> Any ideas as to the way out?

Somewhat complex.  It's been years since I tried to do what you are
doing; please bear with me.

LILO uses at least two, perhaps three different load files before
[unzipping and] loading the Linux kernel.  Each of these files records
the locations of the next, and of any other files it may need, NOT via
the file system, but on a BLOCK-BY-BLOCK basis.  ;-(  It records the
blocks by DISK NUMBER and block number!  So, all of these files heartily
believe that your files are on the first disk drive!

I didn't quite catch why you couldn't install it in situ?  That would
probably be easiest.

Several people tried to convince me that the Linux-executable 'lilo'
program had a way to tell it not to record the way disks were, but to
put a different disk number in.  I tried.  But, even looking at the
'lilo' source code, I was unable to find a way to do this.  [This may
have since changed; I haven't looked at the problem again recently.]

What I ended up doing was writing a simple program.  It went into the
LILO boot area and all of the successive load files, and everywhere that
it found a pointer to a disk block, it changed it from what it was to
what it would be.  Once this was done, of course, the disk was no longer
bootable as it was.  But it was bootable when I put it into its
"permanent" configuration.

Unfortunately, I no longer have access to this program.  But it was
pretty easy to write, once I had examined 'lilo's header files.  It also
encouraged me to try, one day when I have copious free time, to write a
version of Unix 'sash' that doesn't need to know ABSOLUTE BLOCK
ADDRESSES to boot a Linux image!  ;-(

Joe Yao				jsdy tux org - Joseph S. D. Yao