POS system trashing hard drives during install

[John McDonnell]

> From: Warren Block
> On Tue, 22 Dec 2015, John McDonnell wrote:
> 
> > I just downloaded and booted from the NetBSD install disk and was
> presented with a screen I haven't seen in FreeBSD in some time. NetBSD was
> unable to match my hard drive to one detected by the BIOS. I remember
> when pretty much every install of FreeBSD would prompt me with that
> message about the reported geometry not matching. I can't recall why the
> prompt no longer shows up in FreeBSD, but perhaps it could be behind the
> issues I'm having?
> >
> > For comparision, here is what I have found about the geometry:
> >
> > NetBSD reports:
> > Cylinders:   1023
> > Heads:           255
> > Sectors:           63
> >
> > The BIOS by default is set to autodetect the mode for the hard drive and
> reports these settings:
> > Cylinders:   19158
> > Heads:                16
> > Sectors:            255
> 
> None of this has really mattered since drives became larger than... I want to
> say 4G.  The MBR spec said that partitions had to be specified in round CHS
> numbers, but that also is meaningless any more.  Although gpart enforces
> that for compatibility, but it is rare that a BIOS cares.

It seems that the BIOS on these machines is one of those rare cases where it cares. While I'm not sure what gparted reports the drive as after doing the FreeBSD install as I didn't make note of it other than just checking that the sector size was 63. But with the BIOS at least set to LBA mode for the hard drive, even if it differs from what the BIOS reports, it is compatible enough that the computer doesn't lock up and does boot.

> If an MBR partition layout created by bsdinstall does not work, I would clone
> the original drive partitioning with gpart (backup and restore).
> Then install FreeBSD bootcode and format the first partition with UFS.
> Then try to get bsdinstall to see that partition and install to it.

I'm not sure if the partitioning in bsdinstall is working or not as I usually end up using your guide on setting up hard drives for FreeBSD.

So once again, thank you for to everyone for your time. And a special thank you to Warren for your guides. I've used several of them over the years and often refer back to them when looking something up. It also helps that your domain name is somewhat easy to remember.

-- 
John McDonnell
mcdonnjd at pcam.org