From owner-freebsd-questions  Sat Jun 17 15:58:13 1995
Return-Path: questions-owner
Received: (from majordom@localhost)
          by freefall.cdrom.com (8.6.10/8.6.6) id PAA11158
          for questions-outgoing; Sat, 17 Jun 1995 15:58:13 -0700
Received: from ref.tfs.com (ref.tfs.com [140.145.254.251])
          by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id PAA11152
          for <questions@freebsd.org>; Sat, 17 Jun 1995 15:58:12 -0700
Received: (from julian@localhost) by ref.tfs.com (8.6.11/8.6.9) id PAA00702; Sat, 17 Jun 1995 15:57:53 -0700
From: Julian Elischer <julian@ref.tfs.com>
Message-Id: <199506172257.PAA00702@ref.tfs.com>
Subject: Re: SNAP-041295 -> 2.05
To: fiorio@lirmm.fr (Christophe Fiorio, LIRMM 67-41-85-78)
Date: Sat, 17 Jun 1995 15:57:52 -0700 (PDT)
Cc: questions@freebsd.org
In-Reply-To: <199506160752.JAA18370@lirmm.lirmm.fr> from "Christophe Fiorio, LIRMM 67-41-85-78" at Jun 16, 95 09:52:22 am
X-Mailer: ELM [version 2.4 PL24]
Content-Type: text
Content-Length: 1716      
Sender: questions-owner@freebsd.org
Precedence: bulk

> 
> 
> Hi,
> 
> 
> A friend of mine (hello Philippe), says that to upgrade my system I
> must format all my FreeBSD disk and install all from the
> beginning. This in order to use the new slice scheme.
No and yes
The New slice code interprets the same 'on-disk' information
but presents it to the user differently.
Your old partitions can be kept, and unless you specify
'NEWFS' in the install procedure, against each of them, they WILL
be kept.

Having said that, there are advantages to rebuilding the 
filesystems as some optimisations have been added...

You can re-install on just root and usr, and leave the other partitions
alone, then re-zap them later on one at a time
to get the newer file-system layouts..

> 
> I can't believe that! Is there no way to upgrade my system without
> losing all my data? Is this new slice scheme necessary? 
it's compatible .. your friend is slightly confused about the changes..
I have systems running 2.0.5 Alpha on filesystems that were
layed out and partitionned under 386BSD. :)
(I believe I may have Newfs'd them under FreeBSD some time)
It's suboptimal to leave them, but not bad.

> 
> Is there a dirty trick to avoid formating the disk? (e.g. doing only
> a sort of disklabel.). It seems that the bounds of the partitions are
> counted from the beginning of the slice and no more from the beginning
> of the disk.
> 

+----------------------------------+       ______ _  __
|   __--_|\  Julian Elischer       |       \     U \/ / On assignment
|  /       \ julian@ref.tfs.com    +------>x   USA    \ in a very strange
| (   OZ    ) 300 lakeside Dr. oakland CA. \___   ___ | country !
+- X_.---._/  USA+(510) 645-3137(wk)           \_/   \\            
          v