Subject: Re: dev_t changes & partitions
To: Wolfgang Solfrank <>
From: Perry E. Metzger <>
List: tech-kern
Date: 01/16/1998 11:29:26
Wolfgang Solfrank writes:
> > The advantage, as I see it, is that it lets you deal with multiple OS's on
> > an MBR disk. Right now, we look through the MBR for a NetBSD partition,
> > and then look in there for the disklabel for the whole disk disklabel.
> > FreeBSD looks for a FreeBSD partition, and looks in there for a FreeBSD
> > disklabel. Same with OpenBSD and Linux. One problem is that each OS will
> > then basically ignore the other OS's partitions, a bad thing if you want
> > to inter-operate between OS's.
> It will ignore the MBR partitions of the other OSs.  Do you really suggest
> that we implement the disklabel scheme of every other OS in the world?
> _In the kernel_?

Wolfgang, this is actually useful, yes. It makes a considerable amount
of sense for your FreeBSD partitions to "just work" or to be able to
just look at your Linux or Windows paritition without bending over
backwards. This is a serious win for the users.

> IMHO our disklabel should allow for a large enough number of
> partitions,

By definition IT CANNOT.

Imagine you have two NetBSD MBR slices on a disk. BY DEFINITION you
can't fit enough partitions for both sets of partitions into one (if
that makes sense.)