From owner-freebsd-stable@FreeBSD.ORG Mon Dec 6 00:37:33 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A4CC0106564A for ; Mon, 6 Dec 2010 00:37:33 +0000 (UTC) (envelope-from vanopen@gmail.com) Received: from mail-pw0-f54.google.com (mail-pw0-f54.google.com [209.85.160.54]) by mx1.freebsd.org (Postfix) with ESMTP id 72D1D8FC0C for ; Mon, 6 Dec 2010 00:37:33 +0000 (UTC) Received: by pwi10 with SMTP id 10so2166571pwi.13 for ; Sun, 05 Dec 2010 16:37:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:cc:subject :message-id:references:mime-version:content-type:content-disposition :in-reply-to:organization:x-operating-system:user-agent; bh=uZxpNL6Y89StJaAX5z6LpvdiqXUFREJ2EcDugSZIPXM=; b=UPNXIvej4VSv0WaFm6AkMmcS4Tw3fQ4id+ojCf426/YAaqDc7YpUXQYnQzMrR42yvk 9WEe8fE24HNU1r+UuiOwrLRBulnFL15+1NxKcmjmAyD+iO4O05ibnzMDas69eV6S0J5A lH4d7QCv6BmAV9FRUME9WacFd2pSnmZhn0ksM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:organization :x-operating-system:user-agent; b=mPp7sf2Ibo6oONfhfTf0rpklzZe++CIt8bKGeJsyN7ZYBz8gCTbmI0cbV8V7TxP84Z WgLgJkB1Vu9UZ/BYICVzkdRNkE5yE7O3hyvurZTFFLozHIVoD0RizYtu0S40RWnkfLGc anEglXOq5ptbiaDz93+Xt63Cwn6Cc4ThiYo9A= Received: by 10.142.252.3 with SMTP id z3mr4445751wfh.161.1291595852609; Sun, 05 Dec 2010 16:37:32 -0800 (PST) Received: from fbsd.t60.cpu ([221.6.39.130]) by mx.google.com with ESMTPS id e14sm6505290wfg.20.2010.12.05.16.37.29 (version=TLSv1/SSLv3 cipher=RC4-MD5); Sun, 05 Dec 2010 16:37:31 -0800 (PST) Date: Mon, 6 Dec 2010 08:37:19 +0800 From: Yue Wu To: David Wolfskill Message-ID: <20101206003719.GA26050@fbsd.t60.cpu> References: <20101206002620.GA1286@bsd.hasee.cpu> <20101206002924.GE1480@albert.catwhisker.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101206002924.GE1480@albert.catwhisker.org> Organization: China Pharmaceutical University, Nanjing, China X-Operating-System: FreeBSD 8.1-STABLE i386 User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-stable@freebsd.org Subject: Re: boot0cfg -B can't work X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Dec 2010 00:37:33 -0000 On Sun, Dec 05, 2010 at 04:29:24PM -0800, David Wolfskill wrote: > From boot0cfg(8): > > NOTE > Protection mechanisms in the geom(4) subsystem might prevent boot0cfg > from being able to update the MBR on a mounted disk. Instructions for > temporarily disabling these protection mechanisms can be found in the > geom(4) manpage. Specifically, do a > > sysctl kern.geom.debugflags=0x10 > > to allow writing to the MBR, and restore it to 0 afterwards. > Thanks, I remembered that boot0cfg in the previous version can do it without changing the sysctl parameter, maybe it's changed in newer version. -- Regards, Yue Wu Key Laboratory of Modern Chinese Medicines Department of Traditional Chinese Medicine China Pharmaceutical University No.24, Tongjia Xiang Street, Nanjing 210009, China