>> My guess would be that your boot blocks (sectors 1-15 of your boot
>> drive)
(I actually should have written "boot partition" here)
>> are untouched from the sparclinux install, and either they contain
>> SILO themselves or they're loading SILO from elsewhere, some
>> "elsewhere" that didn't get overwritten during the NetBSD install.
> From what you've said, it seems to imply that the process of
> formatting and partition creation that the installer does, doesn't
> revamp all of the disk.

The installer doesn't actually format the disk[%]; it just overwrites
certain pieces of it (partition table, filesystem overhead blocks,
and enough data blocks to hold the installed data.  It ought to install
bootblocks too, and in most <port,version> cases it does, but it
appears in your case it didn't.

[%] It _does_ make a filesystem, which Windows - and DOS before it -
    have caused a lot of people to confuse with formatting.  (On some
    versions of Windows, and DOS before them, make-filesystem command
    was called FORMAT.  This is probably a legacy of the days of
    floppy-disk OSes; then and now, FORMAT *applied to floppies*
    generally _does_ format the disk.)

> If that's the case, would dd'ing from /dev/zero to the entirety of
> the disk do the trick?

Yes.

> It may be a sledge hammer to crack a nut

Yes. :-)

> but I'm assuming that if I drop down to a shell from the installer,
> _prior_ to actually performing the install and do something along the
> lines of
> # dd if=/dev/zero of=/dev/sd0c bs=1024k count=whatever
> this would zap the entire disk contents?

Yes - or at least, the entire host-accessible disk contents, which is
what matters here.

It is severe overkill, and you will have to redo your partition table
afterwards, but in the process of razing the city it _will_ demolish
the shed you want torn down. :-)

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