From owner-freebsd-current@FreeBSD.ORG Mon Jul 20 22:01:23 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A60571065673 for ; Mon, 20 Jul 2009 22:01:23 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.251]) by mx1.freebsd.org (Postfix) with ESMTP id 5CCC28FC0C for ; Mon, 20 Jul 2009 22:01:23 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: by an-out-0708.google.com with SMTP id d14so1201637and.13 for ; Mon, 20 Jul 2009 15:01:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=pkYI9TiPP1cD5czWbXE6Ja/Ls49gZBIHAQWewOCBVeg=; b=v3Xod76Nqvo02DVw1oTEoNyJq6q7lEDgbf0vbSQzZE0ITi5529ePtz8a8cVr5jacNR SKuV1m5SymWgHihkQXRa2YFaBoZcPoh+ukzlgFcXBZ9qQok9KsLP3GpTNE37isBaJ7Rp FJSP1ktIOpJ9o5xPQs7jmdw/Eqw1rsH7dxlAg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=ud7CSf4glHxV+wubf0wZWgLO+TchJb5KMR5G+T+YHNWthgJA5ADvz6+L63pndv7ZxD ZLhPjxkGsViK4RKMMI1qZJcm4D47leJgdp5jAJV/zN5o53SIgRrcsC/MSjKJvkeU5Nuo TFQpJJbkODKcquvZQ1lTZEd6MoDw9HsTU6oTI= MIME-Version: 1.0 Sender: mat.macy@gmail.com Received: by 10.100.92.2 with SMTP id p2mr6827479anb.7.1248127282613; Mon, 20 Jul 2009 15:01:22 -0700 (PDT) In-Reply-To: <4A5D4D25.3040908@ish.com.au> References: <4A5D4D25.3040908@ish.com.au> Date: Mon, 20 Jul 2009 15:01:22 -0700 X-Google-Sender-Auth: e0581bfce1345154 Message-ID: <3c1674c90907201501j42f29bfbl987419edf04b1a8b@mail.gmail.com> From: Kip Macy To: Aristedes Maniatis Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-current@freebsd.org, Jurgen Weber Subject: Re: Problematic upgrade from 7.2 to 8.0 with ZFS file system X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 Jul 2009 22:01:24 -0000 On Tue, Jul 14, 2009 at 8:29 PM, Aristedes Maniatis wrote: > Last night we upgraded one of our servers from 7.2 to 8.0-beta1 using the > freebsd-update tool and following the instructions on Colin's blog. I > believe this problem will occur even if we had used a source update > mechanism. > > The usual upgrade path is to install the new kernel, reboot, then install > world. This fails because when rebooting into the 8.0 kernel with 7.2 > userland, ZFS is unable to properly initialise and the file systems are not > mounted. In our case we are booting with a small UFS partition to load the > kernel, and then mounting /usr /var, etc from ZFS as per these instructions > [1]. > > The problem with ZFS userland being out of sync with the kernel has been > seen before [2] [3]. However now with lots of people running ZFS and > starting to upgrade to 8.0, I think this will bite many more. > > The workaround is to drop into single user mode, mount all the zfs > partitions, and do the userland install. > > mount -t zfs /usr > mount -t zfs /var > mount -o rw tank/root / > > Those mount commands are slightly non-obvious and took a little guessing to > get right. You can't use the 'zfs mount' command since it is broken at this > point in time. > > The other solution is to install userland BEFORE you reboot into the new > kernel, although that may cause its own set of problems. Whatever the final > solution, this needs to be clearly documented and ideally freebsd-update > needs to detect the problem and advise the user about what to do. Do to the large version jump (v6 -> v13) the kernel interfaces aren't backward compatible with the tools. How do you think it could be most gracefully handled? -Kip