[wellylug] Bootloader Problems?

[David Antliff]

On Sun, 18 Apr 2004, Jethro Carr wrote:

> Could it be a problem with my bios not liking grubs format, or
> something?

No, my understanding is the BIOS merely loads data from the master boot
record (MBR - first sector on the hard disk) and 'jumps' to it. If it's
recognisable machine code, then it executes, otherwise an exception is
generated by the CPU. All going well, this bootstrap code usually loads
more code from somewhere else on the disk and continues the execution. The
BIOS does nothing more in this regard.

If LILO works, then GRUB should work too. At least to the point of
initially starting to load and execute the boot loader. Make sure you have
installed something in the MBR - if you only installed to the boot sector
of a partition (the first sector of a partition) then it won't work. The
BIOS typically has no knowledge of partitioning schemes and the associated
partitions' boot sectors. Therefore it only loads code from the MBR, since
this is always at the same physical location on the disk.

I'm not sure marking a partition as 'bootable' really makes any difference
to linux bootloaders. The BIOS certainly doesn't care since it has nothing
to do with partitions anyway, and I don't think GRUB or LILO care either.
They are smart enough to work without that DOS relic.

-- 
David.