Re: about lilo

[Paul E Condon <pecondon@peakpeak.com>]

On Mon, Sep 29, 2003 at 08:22:51PM -0700, Sidney Brooks wrote:
> Please help me to understand lilo. If one loads lilo
> on the root sector of a partition, does this mean that
> it has no affect on the MBR? Exactly, what does it do
> when it is on a partition? Presumably, it specifies
> the kernel to be used on the partition, but how do you
> get to the partition in the first place?
> 
> The reason for these questions is because I want to
> upgrade my kernel without changing the MBR.
> 

Your questions indicate some misunderstanding of the purpose
of lilo. lilo is a program which writes information into the
_boot_ sector of a hard disk or of a partition on a hard disk.
It is designed to give information to the boot loader as to
where, on the disk, the kernel can be found. If you change your
kernel, and want to _use_ your new kernel to boot-up your
computer, you _must_ change the MBR on your disk. lilo and grub
are two popular programs for making this change. I use lilo
because it was the most popular when I got started and I've
learned to use it, mostly. In particular, I've never tried to
use the boot sector on a partition, so I don't know for sure,
but it seems to me that if you put the info about your kernel
in a partition boot sector, you must also put info in the MBR
indicating that the boot loader should look in the PBR. 

The alternative to understanding how lilo works, is to write
critical information to a floppy and boot from that floppy,
but, again, I've never done that so can't advise.

Finally, editing lilo.conf and running lilo is pretty easy,
and should not be something to cause great worry. But, if
you doubt your understanding, don't try until you have
a boot floppy and have successfully booted from it. Then
you can recover, if you make a mistake editing lilo.conf.
The most common mistake is forgetting to run lilo after
editing lilo.conf.

HTH

-- 
Paul E Condon           
pecondon@peakpeak.com