Hello

Thanks for all your valuable info on this issue.

I don't intend to use other OS, but if I understood you correctly, my
current bios partition table would enable me to run 2 more OSs. How I
set up my disklable on my NetBSD partition does not have anything to
do with other partitions.

Since I am now in this position...how do I delete partition 1 and 2?
What tool should I use?

V.


On 07/03/06, James K. Lowden <jklowden@schemamania.org> wrote:
> Vojko Kercan wrote:
> > Below is my partition table (partition 0 is wher NetBSD 3.0 is
> > installed):
> >
> > 0: NetBSD (sysid 169)
> >     start 63, size 188747622 (92162 MB, Cyls 0-11749), Active
> > 1: NetBSD (sysid 169)
> >     start 188747685, size 62926605 (30726 MB, Cyls 11749-15666)
> > 2: NetBSD (sysid 169)
> >     start 251674290, size 69998670 (34179 MB, Cyls 15666-20023/55/1)
> > 3: <UNUSED>
> ...
> > Judging by above outputs, to mount the remaining partitions (1 and 2) I
> > should: mount /dev/wd0h and mount /dev/wd0i, yet mount produces an erro=
r
> > "incorrect super block".
>
> The problem with the term "partition" is its ambiguity.  Berlin was
> partitioned for a long time.  Context is everything.
>
> http://support.microsoft.com/default.aspx?scid=3Dkb;EN-US;Q69912
>
> Keep in mind that the MBR partition table first appeared in MS-DOS 2.0 to
> cope with "big" hard disks i.e., drives larger than the largest filesyste=
m
> MS-DOS could create.  At the time, that meant 15 MB filesystems on 20MB
> hard disks.  That would have been around 1984.
>
> Owing to its age and ubiquity on "IBM PC-compatible" hardware, lots of
> operating systems, including NetBSD, have learned to interpret and respec=
t
> the MBR.  In so doing, they preserve other operating systems' data and
> permit "dual-booting", etc. Like the Geneva Conventions, it mostly
> controls what it's supposed to because not conforming is decidedly
> unneighborly.
>
> The NetBSD kernel does not *use* the MBR partition table, though.  NetBSD
> manages the disk via its disklabel.  Only this and nothing more.
>
> Obviously, if you have more than one OS using the disk, it's a good idea
> if they both have one consistent view of it.  In such a case, you'd want
> your disklabel partitions and your MBR partitions to share (some)
> boundaries.  (Basically, all the disklabel partitions lie within the MBR
> partition assigned to NetBSD.) But you're not trying to do that.
>
> Your MBR partition 0 covers the whole disk, which you intend solely for
> NetBSD.  You should remove partitions 1.and 2 because they overlap sector=
s
> with 0.  If anything ever tried to use them, they'd step on your NetBSD
> system like a bulldozer on a putting green.
>
> Then set up your disklabel according to your needs.  You seem to know wha=
t
> you want,so I won't advise you.
>
> HTH.
>
> --jkl
>