From owner-freebsd-questions@FreeBSD.ORG Tue Aug 12 20:32:34 2014 Return-Path: Delivered-To: freebsd-questions@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 ESMTPS id B3F50D1A for ; Tue, 12 Aug 2014 20:32:34 +0000 (UTC) Received: from mail-pa0-x22b.google.com (mail-pa0-x22b.google.com [IPv6:2607:f8b0:400e:c03::22b]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 898B62E47 for ; Tue, 12 Aug 2014 20:32:34 +0000 (UTC) Received: by mail-pa0-f43.google.com with SMTP id lf10so13644023pab.2 for ; Tue, 12 Aug 2014 13:32:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=3PUJ30c5as7zKDF2tJwDBIZHgA0z9RrEEVpvWW9QbrU=; b=vyWt3NbfWqNv0v7qdiAGR3+zBhogO8E0G+ibEFIUNVXW35z48qoBWJ9oTk4iyMdKON 3ecHoeO4LQ4mofDA7/+zJli7fZJzXVq0EsHp8Q6qDjZ3UI/aRRVrUS5bsfYFT7Gpn4RX C6qo65v0cFrv6i3iCdyrBxvoUrNzOE0VKxK4jgOta7EEd2QZtYW9Tj7VTmKPAqpaVfKo zjAxXX7JzBA1VLZw9qkwB+atZj7d7s0gSA+3bZbyvXdOziko/c1XuXIi5d5b88NUc8SJ y6zPiSBzldLemMXcIwMlq8D17VGTSg2oi3jD+OF9gGsIPwAEsHe5djbndtD/X0Zvd9Am 5svA== MIME-Version: 1.0 X-Received: by 10.68.191.34 with SMTP id gv2mr59220pbc.13.1407875554243; Tue, 12 Aug 2014 13:32:34 -0700 (PDT) Received: by 10.70.118.132 with HTTP; Tue, 12 Aug 2014 13:32:34 -0700 (PDT) In-Reply-To: References: <20140812193419.GB7166@slackbox.erewhon.home> Date: Tue, 12 Aug 2014 15:32:34 -0500 Message-ID: Subject: Re: Problems with dump and restore From: Adam Vande More To: Andrew Hamilton-Wright Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 Cc: Roland Smith , FreeBSD Questions X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Aug 2014 20:32:34 -0000 On Tue, Aug 12, 2014 at 3:14 PM, Andrew Hamilton-Wright < AHamiltonWright@mta.ca> wrote: > > Sorry, a bit of a follow up after some reading, as the soft-update > bit was itching in my memory... > > > > On Tue, 12 Aug 2014, Roland Smith wrote: > > In 2011, a problem was found with snapshots in combination with soft >> updates *and* journaling (SU+J) hanging the machine. At that time the >> recommendation was to switch off journaling. >> According to https://wiki.freebsd.org/NewFAQs: >> >> If you want to use snapshot (dump -L) then disable the soft updates >> journal for that filesystem. >> > > I have just realize that the soft update journal (newfs option -j enable) > is actually not in play here, however "soft updates" (option -U) is. My > understanding of the referenced bug: > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=160662 > is that it is specifically referred to _journaled_ soft updates as being > a danger, but soft updates using -U are not referred to by this bug. > > Is that your understanding as well? > > I believe that when I set up the filesystems for this machine in the first > place, I specifically ensured that "-j disable" was chosen, for exactly > this reason -- however my logbook does not contain enough detail for > me to be sure. > > > To be clear then, do I understand that your filesystem options include > neither "-j enable" nor "-U"? As stated in the bug, only SU+J needs disabling for live dumps. However, since the bug doesn't even apply to your situation, this is a red herring. -- Adam