Subject: Re: sysinstall changes
To: Michael Graff <>
From: None <>
List: tech-install
Date: 09/17/1998 21:47:41
Michael Graff <> writes:

> writes:
> > I once took a stab at making a better more acurate sysinst.  The patches
> > are against a 0914 tree.  I've not rebuilt it in a month or so and
> > there are a few merge conflicts.  Try it you make like it.  These are
> > x86 changes only
> I glanced at the changes, and have a few comments.
Sure, that's what I wanted.
> Will people understand what "megabytes rounded to BIOS cylinders"
> means?
One of the reasons that sysinst is such a killer problem is that there
probably has to be bit of explanation in the installation manual that
better explains this cryptic phrase.  Of course, if we can spare the
space on the install floppy, we can make sysinst more verbose and have
a "menu" that explains this.

On the otherhand, megabytes are normally rounded to cylinders.  Is
this something that needs to be explained too and why not?

> Really, there should be two steps.
> 	(1)  creating the NetBSD BIOS partition.  This is rounded to
>              BIOS cylinders.
> 	(2)  within the NetBSD portion of the disk, round things to
> 	     the drive's real geometry when possible.
This is actually what the code does.  It would take an extra menu to
make this distinction, but it might well be worth it.

> Of course, considering most SCSI and most IDE drives report bogus
> "physical" geometry...  (2) might not be important, but (1) still
> is.
Point of clarification:  The reason we round to BIOS partitions is to
live compatibly with other OS's on the disk.  BIOS does not care if
you start in the middle of a cylinder and in the middle of a track.
You just have to use its definition of geometry and you have to
specify the start in C/H/S correctly.

> --Michael