Subject: Re: SMP and dual boot with FreeBSD?
To: Le Zhang <>
From: Robert Elz <kre@munnari.OZ.AU>
List: netbsd-users
Date: 09/27/2004 18:02:43
    Date:        Mon, 27 Sep 2004 11:14:37 +0100 (BST)
    From:        Le Zhang <>
    Message-ID:  <>

  |   Recently I got a dual PIII machine and want to
  | install NetBSD 1.62 on it. Does that version support
  | SMP yet?

no, you need NetBSD 2 for that (currently a release candidate for
that exists, but it should be very stable and safe to use if you
want to try it rather than 1.6 versions).

  | If the answer is no, I plan to install both
  | FreeBSD (for SMP) and NetBSD. Is it possible to share
  | the /home partition between the two BSDs? 


Use FFSv1 for safety, rather than FFSv2 (which is probably the default
on FreeBSD these days - might work on NetBSD as well, but FFSv2 is rarely
used on NetBSD so far), and for simplicity, put the /home inside the
FreeBSD partition.

Then, get the absolute block numbers (start & size) from FreeBSD, and
edit those into the NetBSD label.

I've done that in the past (been a long time since I needed to, but I
have done it) and this works just fine.

FreeBSD prefers (or used to prefer) not to reference outside the MBR
partition (or partitions) allocated to it.  NetBSD has no such scruples.
Hence reaching out from NetBSD into the "FreeBSD space".   (For what it
is worth, I used to share swap space just the same way - install NetBSD
with no swap space allocation, then edit the label so swap space is
the same space as FreeBSD puts its swap).