Re: BSD disklabel partition letters in NetBSD

["Rocky Hotas" <rockyhotas%post.com@localhost>]

> Sent: Friday, October 05, 2018 at 1:55 AM
> From: "Robert Elz" <kre%munnari.OZ.AU@localhost>
> To: "Rocky Hotas" <rockyhotas%post.com@localhost>
> Cc: "NetBSD Users Mailing List" <netbsd-users%netbsd.org@localhost>
> Subject: Re: BSD disklabel partition letters in NetBSD

[...]

>
> You can put swaps space in any partition you like, and have as many of them
> as you like

Ok!

> What you might want o be careful about is using partition b for something other
> than swap. That should work as well, there's nothing truly magic about 'b',
> but there is just a possibiliity that some script, somewhere, mighht simply
> assume that if it needs to add some swap space, it might just decide to simply
> use the b partition, if one exists, without asking first, and destroy anything
> else that is there.

This is important to remember, thank you.

> The one case wherte it is needed (to have 2 different swap areas) would be
> is system A was to be a XEN Dom 0, and system Bis to be a DomU client
> (or vice versa of course) - that is, when both systems are to be running at
> the same time,

It's a very peculiar case, however, got it.

> Where to mount things is in the fstab in the root, wherever that is - certainly
> not in the disklabel - but the filesystem (at least ffs filesystems) do
> contain a "last mounted on" field.
[...]
> One thing to watch when mixing NetBSD and FreeBSD - FreeBSD disklabels
> (which would be in the FreeBSD root partition normally, just as the NetBSD
> one is) are relative to the MBR partition (or slice)
[...]
> FreeBSD treats
> (or did last time I looked) MBR partitions (slices) as if they were different
> drives.
>
> If you want to put both NetBSD and FreeBSD on the same drive, then I'd
> suggest using MBR partitions as a way to keep yourself sane.

Thanks for considering all these specific and not-obvious cases, where attention
must be paid.
According to this discussion, it should be avoided to use BSD disklabel for
NetBSD and FreeBSD on the same machine: despite it seems very bizarre, MBR could
be the best choice.

Rocky

>
> kre
>
>