From owner-freebsd-stable@FreeBSD.ORG Sun Nov 3 08:07:13 2013 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id C6BA166C for ; Sun, 3 Nov 2013 08:07:13 +0000 (UTC) (envelope-from garbytrash@gmail.com) Received: from mail-pd0-x22c.google.com (mail-pd0-x22c.google.com [IPv6:2607:f8b0:400e:c02::22c]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id A559D22D9 for ; Sun, 3 Nov 2013 08:07:13 +0000 (UTC) Received: by mail-pd0-f172.google.com with SMTP id w10so5530406pde.17 for ; Sun, 03 Nov 2013 01:07:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=aIXi///WRRHp9LPCnhPYpyYxYGRjwU+bJ3q8RL59vYw=; b=buAelel3xCy/t/vHgSfPSs6aBUvNXTR4yOSMCTGttzktXXkMbwjo9pPdRy/FiIfBMH wFc/SdEwAUNaLBLE7y33+fUupdq+CAq8pRwVVrSZqSJURgIKsfnqGps5qnYgEsYkglsR evWDMJBUaDZ86f2OrD+v2KEHxotBjoEy9/SfwXETrrk0n8XjMFVkg7ESLfHSZCR9+Kci ZqR9fHk0UrosAtNJcsZaL5hVnCiVI3CqPTzLnHt79bHsHZ0JpfFz5JKhL/E5uj2VWF3s E3LlwA81iPCXgaqkKzPTlyjZbjGyhDEu4yuO7tmaebsKFRRxVaNzJm2R3Fz4bC+GrQN8 bkhg== MIME-Version: 1.0 X-Received: by 10.68.211.39 with SMTP id mz7mr11751007pbc.90.1383466033189; Sun, 03 Nov 2013 01:07:13 -0700 (PDT) Received: by 10.66.142.167 with HTTP; Sun, 3 Nov 2013 01:07:13 -0700 (PDT) Date: Sun, 3 Nov 2013 09:07:13 +0100 Message-ID: Subject: HDD-manufacture induced ZFS limitations From: Zenny To: freebsd-stable@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 03 Nov 2013 08:07:13 -0000 Hi: PROBLEM I came across a very weird situation because HDD-manufacturer counts HDD space according to metric system instead of multiplication of 1024 (2^10). This mismatches the space capacity between what OS filesystems calculate HDD space. Secondly, each HDD manufacturer has different total byte size for what they claim as the same sized HDDs. With the above two scenarios, it poses a nuisance to replace a corrupted HDD with another HDD from another manufacturer even though they claim that they are of the equal size, but differs by a few bytes. Thus, zfs does not accept the new HDD. SOLUTION A way around is to create a sparse zfs dataset at the beginning, according to the HDD-manufacturer defined metric system of HDD space measurement at the power of 10 rather than 2^10. BUT ANOTHER PROBLEM However, I came across another odd situation with the bsdinstaller with FreeBSD 10-Beta2 which has an option to install root in zfs. The bsdinstaller script is flawless as it is. But it does not address the disksize mismatch problem as stated above. Any workaround will be appreciated! It would be a nice feature if the new bsdinstaller in FreeBSD10 allows the user first to make a sparse zfs dataset before installing root in zfs. Thanks! /z