Followup Q to "IBM 120 G IDE -- problems"

[Jerry McAllister]

> 
> Hi,
>      Well, I've got my 120G disk up and running and
> now I'd like to understand something odd.
> 
>      I went into /stand/sysinstall to put down the
> partition and slice tables and the FS and found that
> it determined the geometry (cyl/head/sectors) as
> 15107/255/63 .  Since it warned that the values must
> match the BIOS values, I set them to the 59131/16/255
> that the BIOS reports.  It rejected this entry and
> went back to its own.  I also tried the values
> reported
> by the ata driver on startup; these too were rejected.
> 
>      Since it's working (with about 117G -- that's
> Gi_b_abytes) it must be OK (famous last words!) but
> what's going on here?  Why does it demand the values
> reported by the BIOS if it will refuse them, and why
> does the driver come up with another set of values,
> also unacceptible to the disklabel/fdisk machinery?

Someone else can answer with more detailed information,
but in general, geometry is virtual in "modern" large
disks and drivers.   They don't map one to one.  Probably
messages saying they must match are vestigial.

////jerry

> 
>                                      Mark Terribile
>