lilo: "not the first disk"

[Harvey Fishman]

On Tue, 8 Sep 1998, Jim Thompson wrote:

> >>>>> "Louis" == Louis Cheung <Louis at atmosphera.com.au> writes:
> 
>     >> Finally after the installation, I had the problem to make lilo
>     >> use the MBR of the /dev/sda, it kept telling "not the first
>     >> disk",
> 
>     Louis> About your problem, it bother me too. But I found a work
>     Louis> around.  You said "I was able to mount the SCSI-disk from my
>     Louis> older IDE-drive."  The problem is your IDE drive, Linux think
>     Louis> it is the first disk.  If you want to boot from /dev/sda,
>     Louis> than first unplug the IDE cable from your IDE HDD (disable
>     Louis> them under BIOS will NOT do this trick).  Re run lilo, it
>     Louis> should not have the problem again.
> 
> I know this is a little off-topic, but since it came up, I'll ask... 
> 
> Does anyone know how to avoid the above problem, and get lilo to
> recognize the SCSI disk as the boot ("first") disk in a mixed IDE/SCSI
> system?  I had this problem myself, and pored over the lilo man page
> looking for a workaround but found none.  That version of lilo, at
> least, won't install a boot record to a SCSI disk if there's an IDE disk
> present.  Perhaps my lilo is old?
> 
> BTW, with some BIOSes disabling both the disk and the IDE controller
> will do the trick -- you don't have to unplug the IDE drive.  This is
> true of the Award BIOS on my old Asus mobo.

This is not a LILO problem at all, but a planar BIOS one.  The planar BIOS
will transfer control someplace at the end of POST.  The classical places
are the first sector of the the first track of the A: floppy if there is
one in place.  If not, then the first sector of the first track of the
first fixed disk.  Since ST-506 interfaced disks generally use drivers
located within the planar BIOS while SCSI drives generally use drivers
loaded from adapter ROM toward the end of POST, if there is an ST-506 drive
it will precede any SCSI drives.

Modern planar BIOSii usually allow you a lot more flexibility in the choice
of the order of seeking devices to transfer control to.  My AMI planar BIOS
in a SuperMicro system board allows a list of up to four devices to try for
a boot device.  (Actually, I have the primary set to floppy, the secondary
set to SCSI, and the tertiary and third and fourth choices disabled.)  But
I think that the simplest way around this is to use Boot Manager from IBM
OS/2, and place that on the first fixed disk whatever that is.  Boot
Manager can vector you to any drive which it can see...i.e. any drive for
which some driver is available at the time that Boot Manager executes.  It
also allows you to choose your operating system.  Though LILO can probably
do the same thing.  I use Boot Manager as my primary tool to choose between
NT and Linux.  I use LILO as the seconday loader for Linux.

Harvey

----------------------------------------------------------------------------
 Harvey Fishman   |
fishman at panix.com |           A little heresy is good for the soul.
  718-258-7276    |


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