From owner-freebsd-fs@FreeBSD.ORG Thu Apr 29 16:47:19 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0FB081065670 for ; Thu, 29 Apr 2010 16:47:19 +0000 (UTC) (envelope-from julianelischer@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id 9053E8FC0A for ; Thu, 29 Apr 2010 16:47:18 +0000 (UTC) Received: by fxm15 with SMTP id 15so1244638fxm.13 for ; Thu, 29 Apr 2010 09:47:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:subject:references:in-reply-to :content-type:content-transfer-encoding; bh=Eri90GVffxXbKuSdFRI425bI78ZJ0MpWVMI5w5EBw4E=; b=WkA6EJXlAB25LHsisFSWDLcaQwtujjHtdCzekCou0tIpq7hRbIsZsW7FMN3Ytct/jM fmg3LzAo48Dj8j/eb+trxVZEhlKG2AVdkgGxoMRIyfbVQ69QdHgsYmOP0fb6NeFrUhw2 W4RsgDTggNbv0HCFK948rJG6ByBHi64y3sZeo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:subject :references:in-reply-to:content-type:content-transfer-encoding; b=j2B9rRXkqlJprEARdojKedHXGBBOxajUtngEoE9/WC/8MJh7VL4/6qmoC40D3G95Mu FKyc84wRQojxEiQIP4KftjNjo8P+bPwOQIIgAcdHPIUyxeCPjJ4Z+xAJVf6+DErRXLLb JWE9Z2a28Dc/fHVoAPM3HRBIWeMkVn7VmmkBQ= Received: by 10.87.48.34 with SMTP id a34mr1941721fgk.2.1272559627666; Thu, 29 Apr 2010 09:47:07 -0700 (PDT) Received: from julian-mac.elischer.org (h-67-100-89-137.snfccasy.static.covad.net [67.100.89.137]) by mx.google.com with ESMTPS id e11sm12641578fga.13.2010.04.29.09.47.02 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 29 Apr 2010 09:47:03 -0700 (PDT) Sender: Julian Elischer Message-ID: <4BD9B7FD.1010409@elischer.org> Date: Thu, 29 Apr 2010 09:46:53 -0700 From: Julian Elischer User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.4; en-US; rv:1.9.1.9) Gecko/20100317 Thunderbird/3.0.4 MIME-Version: 1.0 To: Andriy Gapon , freebsd-fs@FreeBSD.org References: <4B9FD6E0.5000303@icyb.net.ua> <4BD9B16A.10606@freebsd.org> In-Reply-To: <4BD9B16A.10606@freebsd.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Subject: Re: few ideas for zfsloader X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 29 Apr 2010 16:47:19 -0000 On 4/29/10 9:18 AM, Andriy Gapon wrote: > > So, right now, I do not see a way to properly support nextboot with ZFS. > We probably should emit some warning when nextboot.conf is created on ZFS that > there will not be automatic recovery if kernel boot fails. > > Some really weird alternative ideas: > 1. Write nextboot flag in some other place (NVRAM, special sectors of HDD) this is what nextboot originally did before it was broken^H^H^H^H^H^H rewritten. I stored the information in sector 1 (not 0) of the drive. One version I never finished stored it in a special 'nextboot' partition. > 2. Use time-limited nextboot - e.g. there is a timestamp in nextboot.conf > and it is honored until the timestamp expires. > But I won't seriously consider these. the timestamp idea good. I considered doing it. myself for the original nextboot. It may be annoying having to wait 10 minutes before recovering from a bad upgrade, but it would be simple, and better than not recovering.