From owner-freebsd-questions@FreeBSD.ORG Wed Dec 2 15:30:11 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 7CAA61065672 for ; Wed, 2 Dec 2009 15:30:11 +0000 (UTC) (envelope-from fbsdlists@gmail.com) Received: from mail-pz0-f176.google.com (mail-pz0-f176.google.com [209.85.222.176]) by mx1.freebsd.org (Postfix) with ESMTP id 42F228FC0C for ; Wed, 2 Dec 2009 15:30:11 +0000 (UTC) Received: by pzk6 with SMTP id 6so221686pzk.29 for ; Wed, 02 Dec 2009 07:30:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=mRXGAEy5T0eMsDNnITnWPjPhmpG0tukjt8A5cZ5RtGM=; b=DZF9SJMCKjeGxxUtxNWhPB5hyOh4usJTd16N9aTkm3Vt5E4nm26IgWyeqHogTNELF1 ljCUyWBzCDSUJOJoDNj+rglziqortcu2wShOQNS+pax2Qjdp8SutsiIFvtaQ83npK44N 7ns3u2o8NT7Ec6W4T0MeZp4Tp85pC1/9/66cQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=LcaqrkIFbNdCgP84vj4N1bhPo7wJoCGFkIXb/jK04oR3eUn/QnNPvbk+vINk4NAFPx G/UJiI5/oxA42/7ymbKGsFv5IEN/r0uAnpI12tsi39Wufl0tVvOdz8IEHmaeMVjfCIgV Kq2om+XvH0rwTKBpNjDVtjK1UplTjVM1bNU9E= MIME-Version: 1.0 Received: by 10.142.195.18 with SMTP id s18mr27743wff.50.1259767810713; Wed, 02 Dec 2009 07:30:10 -0800 (PST) In-Reply-To: <1789c2360911280928t1e6e7b06p707abc1131f82bef@mail.gmail.com> References: <1789c2360911280928t1e6e7b06p707abc1131f82bef@mail.gmail.com> Date: Wed, 2 Dec 2009 10:30:10 -0500 Message-ID: <54db43990912020730u6d43e0caib7cc32b5aa80b7ce@mail.gmail.com> From: Bob Johnson To: Peggy Wilkins Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Cc: freebsd-questions@freebsd.org Subject: Re: 8.0-RELEASE and "dangerously dedicated" disks X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 02 Dec 2009 15:30:11 -0000 On 11/28/09, Peggy Wilkins wrote: > Can someone elaborate on what exactly this statement in the 8.0 > detailed release notes means? > > http://www.freebsd.org/releases/8.0R/relnotes-detailed.html#FS > >> 2.2.5 File Systems >> >> =93dangerously dedicated=94 mode for the UFS file system is no longer >> supported. >> >> Important: Such disks will need to be reformatted to work with this >> release. > [...snip...] > > It doesn't make sense to me that "dangerously dedicated" could have an > impact on UFS filesystems specifically. A partition table is just a > partition table, regardless of what filesystems might be written on > disks, yes? Am I misunderstanding something here? > Unless someone has changed the meaning of the term in the last few years, a "dangerously dedicated" disk is one that has the FreeBSD file system on it with no partition table. It is basically an artifact of the pre-Microsoft origin of BSD (there were reasons it stayed around, but they ought to be ancient history by now). Since UFS is the standard FreeBSD filesystem, DD disks contain UFS filesystems almost by definition. So, to get to the main point of your confusion (and unless I am the one that is very confused), "dangerously dedicated" disks do not have partition tables. That's what makes them dangerous. It confuses things that expect to find a partition table. If your partition name has an "s" (slice number) in it (e.g. ad2s1a) it is not "dangerously dedicated". A "DD" disk partition would have a name like "ad2a" with no slice number. At least, that's the way it used to be. I quit using DD disks years ago when it became clear to me that the unintended side effects aren't worth the few bytes you save. Every once in a while a BIOS, or a utility, or something else pops up that expects to find a partition table and gets confused without it. It appears that it has happened again. > Thanks for helping to clear up my confusion... I hope I helped. --=20 -- Bob Johnson fbsdlists@gmail.com