Jason Majors wrote, on 1/24/02 @ 12:19PM
> I'll probably just re-install, putting XPernicious on a 10G
primary
> partition, and Debian on a 10G extended partition with /, Home, and
Swap
> on logical partitions. Am worried about that "boot must be on first
1024
> cylinders" thing, though.........
Not a problem. If you put lilo in the MBR (the default choice I
believe), it
doesn't matter where your debian /boot is.
_____________________________________________
That's heartening, Jason. Perhaps you can decipher the below, and
tell me where I'm missing whatever I'm missing.
Keep in mind, that although I have a good background in *analog*
communications electronics, and am studying very hard, I never even
looked at a computer 'til about 2 months ago......
Bruce
>From the Debian Installation Manual, at the end of 4.2.1
[I have a new Gateway w/ 128 RAM and a 20G Ultra ATA HD. Can set BIOS to
boot from CD]
The last issue about the PC BIOS which you need to know is that your
boot partition, that is, the partition containing your kernel
image,
needs to be contained within the first 1024 cylinders of the drive,
_unless_ you have a BIOS newer than around 1995-98 (depending
on the
manufacturer) that supports the ``Enhanced Disk Drive Support
Specification''. Both Lilo, the Linux loader, and Debian's
alternative `mbr' must use the BIOS to read the kernel from the
disk
into RAM. If the BIOS int 0x13 large disk access extensions are
found
to be present, they will be utilized. Otherwise, the legacy disk
access interface is used as a fallback, and it cannot be used to
address any location on the disk higher than the 1023rd cylinder.
Once Linux is booted, no matter what BIOS your computer has, these
restrictions no longer apply, since Linux does not use the BIOS for
disk access.
If you have a large disk, you might have to use cylinder
translation
techniques, which you can set from your BIOS setup program, such as
LBA (Logical Block Addressing) or CHS translation mode (``Large'').
More information about issues with large disks can be found in the
Large Disk HOWTO
(http://www.linuxdoc.org/HOWTO/Large-Disk-HOWTO.html). If you are
using a cylinder translation scheme, and the BIOS does not support
the
large disk access extensions, then your boot partition has to fit
within the _translated_ representation of the 1024th cylinder.
The recommended way of accomplishing this is to create a small
(5-10
MB should suffice) partition at the beginning of the disk to be
used
as the boot partition, and then create whatever other partitions
you
wish to have, in the remaining area. This boot partition _must_ be
mounted on `/boot', since that is the directory where the Linux
kernel(s) will be stored. This configuration will work on any
system,
regardless of whether LBA or large disk CHS translation is used,
and
regardless of whether your BIOS supports the large disk access
extensions.
