From owner-freebsd-current@FreeBSD.ORG Mon Jul 20 22:56:45 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 0FD631065672 for ; Mon, 20 Jul 2009 22:56:45 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: from mail-yx0-f181.google.com (mail-yx0-f181.google.com [209.85.210.181]) by mx1.freebsd.org (Postfix) with ESMTP id BCF618FC17 for ; Mon, 20 Jul 2009 22:56:44 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: by yxe11 with SMTP id 11so4217789yxe.3 for ; Mon, 20 Jul 2009 15:56:44 -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=EcEMYlruMKRbmRW8BGhrMOyaBUyBq92k5zC8Cc47wfc=; b=jK3/VjRzmqLMxqnU0fM4IZOiIGGeBQrG88CWnd7JBmmvTRAsTjU5FKsgl9Ln36jDQr GT9BPhloRwDvnQnptos21GvQejkFigdd4J27LR328QWJiY1HhR16HwMlbu7oeZQh8ajn HQDv5nV4GQCvbrd4HCJcsImU1oaMfk3NA5l6w= 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=r1qyGMf6jREBaENkb2mLf3AVdv8vhDw004QnPNl2ZZmjaUdzylMh9FzgYLFLgaiDzT Aha4WgCT2SVeNf6qVdQakiO+rzuYWxG4iv8gOO3lTs2wvxl6B1WTjcaA/51wvDEBJpWI pAgsNrGM0/fHTTcFZbajDGessq/gDyYlY3K3c= MIME-Version: 1.0 Sender: mat.macy@gmail.com Received: by 10.100.41.6 with SMTP id o6mr6870267ano.92.1248130604211; Mon, 20 Jul 2009 15:56:44 -0700 (PDT) In-Reply-To: <4A64F35E.6070501@ish.com.au> References: <4A5D4D25.3040908@ish.com.au> <3c1674c90907201501j42f29bfbl987419edf04b1a8b@mail.gmail.com> <4A64F35E.6070501@ish.com.au> Date: Mon, 20 Jul 2009 15:56:44 -0700 X-Google-Sender-Auth: be8a122e649f1e6b Message-ID: <3c1674c90907201556n7dbd385fucb2d49aa2b1a1416@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 22:56:45 -0000 > > I honestly don't know how the right way to solve the problem, but here are > some ideas: > > * the kernel ABI *should* be compatible with userland tools at least one > major version backward. I understand that this might now be impossible, but > it is possible to bring back enough of the old ABI to allow for zfs to > mount? No. There are many issues that have much higher priority. > > * freebsd-update could automatically detect this situation and install the > new zfs userland at the same time as the new kernel Need to talk to the update maintainer. > * lots of of clear documentation about what course of action a user should > follow if they are performing a source update. Should the recommendation be > changed to install userland *before* rebooting, and then immediately reboot > before some of that userland explodes against the old kernel in memory? UPDATING explicitly states that the two need to be in sync or the user tools will not work. > The existing recommendation is based on the fact that the new kernel will > continue to work after reboot with the old userland. > If that assumption is > not always true then the whole FreeBSD installation process needs > rethinking. I don't think so. It is well understood that ZFS is an external code base, and like any third party application, users need to to inform themselves when updating. Just because it works fairly well, I don't think we should mislead ourselves in to believing that all the rough edges can be removed in the near future. -Kip