From owner-freebsd-questions@FreeBSD.ORG Sun Sep 22 15:03:37 2013 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id E0F7AEED for ; Sun, 22 Sep 2013 15:03:36 +0000 (UTC) (envelope-from atar.yosef@gmail.com) Received: from mail-wi0-x234.google.com (mail-wi0-x234.google.com [IPv6:2a00:1450:400c:c05::234]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 7B60E2631 for ; Sun, 22 Sep 2013 15:03:36 +0000 (UTC) Received: by mail-wi0-f180.google.com with SMTP id hj3so1307586wib.1 for ; Sun, 22 Sep 2013 08:03:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:to:cc:subject:references:date:mime-version :content-transfer-encoding:from:message-id:in-reply-to:user-agent; bh=kFFzcp9O65qKh6fVOMktmsqH/Qp7skR/jJ0qJ7sccfc=; b=qKN8sL31PD37rmtyLpnqW/ADt5YGoOKrzkWjQbqvM7sHv6XSZB3c59svKwrwC1PSqr dSms/KrutuwrbkPCN3M+1961FeQeCSxN1HFx4Dn1SRmfmrnpZqGnp7Agy1tNXQBmHOTL UCAkE3GdFCRVo7xaImQpCEs246w/Lp9oEwvhyH4Y9RtsZssvFtNp62/hGbVh2Pmftgyc wnSkOu+j/4kQKV2mU1D13DW8aMIWoW9jYv/Rh6lIKPiQ4WF+6AL0LhO/rncNAMd+/ICa cPrXacY282lAYWeSRE4wvkYiAWbZHEJN+u+HeYdNI3CNN2wc5SLPZg5LTIVD0PS92kLK HwQw== X-Received: by 10.194.120.68 with SMTP id la4mr1759072wjb.33.1379862214807; Sun, 22 Sep 2013 08:03:34 -0700 (PDT) Received: from localhost ([95.86.71.242]) by mx.google.com with ESMTPSA id i8sm19170410wiy.6.1969.12.31.16.00.00 (version=TLSv1 cipher=RC4-SHA bits=128/128); Sun, 22 Sep 2013 08:03:34 -0700 (PDT) Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes To: "Warren Block" Subject: Re: dangerously dedicated physical disks. References: Date: Sun, 22 Sep 2013 18:03:31 -0000 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: atar Message-ID: In-Reply-To: User-Agent: Opera Mail/12.16 (Linux) Cc: "freebsd-questions@freebsd.org" X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Sep 2013 15:03:37 -0000 Thank you very much about your efforts to explain me in detailed the 'dangerous dedicated' term. Regards, atar. Warren Block wrote: > On Sun, 22 Sep 2013, atar wrote: > >> During the reading of the FreeBSD handbook, I've encountered at the >> term 'dangerously dedicated' regarding physical disks and the author of >> this chapter in the FreeBSD handbook didn't think this term need more >> clarity. so for newbies like me in the FreeBSD world I want to ask: >> what's the 'dangerously dedicated' term meaning by? > > The term refers to a disk partitioned with only the BSD disklabel > partition table: > > disk ada0 > partition "a" (ada0a, /) > partition "b" (ada0b, swap) > partition "d" (ada0d, /var) > partition "e" (ada0e, /tmp) > partition "f" (ada0f, /usr) > > It's "dangerous" because that partitioning format is rare outside of > BSD-based systems. Disk utilities may not recognize it, and could > damage it. > > Most of the rest of the world used MBR partitioning, which allowed up to > four MBR partitions (called "slices" by FreeBSD) per disk. > > Since four slices is not enough for the standard FreeBSD disk layout, > with /, swap, /var, /tmp, and /usr, the standard procedure is to use MBR > partitioning, with the MBR partitions ("slices") being sub-partitioned > by a BSD disklabel. > > disk ada0 > MBR slice 1 (ada0s1) > partition "a" (ada0s1a, /) > partition "b" (ada0s1b, swap) > partition "d" (ada0s1d, /var) > partition "e" (ada0s1e, /tmp) > partition "f" (ada0s1f, /usr) > MBR slice 2 (ada0s2) > ... > > Yes, one partition format inside another. It only seems complicated > because it is. > > GPT is the new partitioning format, which makes things much simpler by > being capable of up to 128 partitions in the standard configuration. > With GPT, there is no reason to use BSD disklabels at all. > > disk ada0 > GPT partition 1 (ada0p1, bootcode) > GPT partition 2 (ada0p2, /) > GPT partition 3 (ada0p3, swap) > GPT partition 4 (ada0p4, /var) > GPT partition 5 (ada0p5, /tmp) > GPT partition 6 (ada0p6, /usr) > > Summary: "Dangerously dedicated" partitioning has no unique advantages. > Use GPT when possible, use MBR/disklabel when necessary.