From owner-freebsd-questions@FreeBSD.ORG Tue Feb 18 05:32:37 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 B8BCB6E8 for ; Tue, 18 Feb 2014 05:32:37 +0000 (UTC) Received: from mail-lb0-x22d.google.com (mail-lb0-x22d.google.com [IPv6:2a00:1450:4010:c04::22d]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 3E2371D56 for ; Tue, 18 Feb 2014 05:32:37 +0000 (UTC) Received: by mail-lb0-f173.google.com with SMTP id s7so10324976lbd.18 for ; Mon, 17 Feb 2014 21:32:34 -0800 (PST) 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:cc :content-type; bh=Y2+uhIufyUt/YtG0WHdlejnRkqBgcUWo9UZprg+DliU=; b=JgdMPmrQytCCxxhaL2Mmpn0Vo/kvWK7exOjwJknKeLbyTrz1d6l3d0cmmW4yAPxAup jyIWMtz0Rvu4R6/+DKWyDMqnFFnso/MobBq1P3W20X1Pb3qijwYTJ+O+x9BUXwyE3XiW c5ppRrgosdH4ITTfKdFbENtSmk6X2/YoktauYy9s58dq+mnVX6YVTWi5OgvwSb9RWL+1 g+Agt76HKdo/uCL/lNFOCG7yyj1uPMwyna4uuWsjKGIOK3ess8QjJpoLE4if7bNroR88 bL+RXbivWqClmXtHCnbF6cUk/PiDsju01rgPg6GiK5C9JJ/tMuTh7ERO2jUK6/1TOwzN XGQw== MIME-Version: 1.0 X-Received: by 10.152.87.228 with SMTP id bb4mr20538041lab.15.1392701553941; Mon, 17 Feb 2014 21:32:33 -0800 (PST) Received: by 10.112.5.193 with HTTP; Mon, 17 Feb 2014 21:32:33 -0800 (PST) In-Reply-To: <20140215221202.GA25183@neutralgood.org> References: <20140213132836.5c04a470.freebsd@edvax.de> <20140215221202.GA25183@neutralgood.org> Date: Tue, 18 Feb 2014 09:02:33 +0330 Message-ID: Subject: Re: Fwd: how to mount r/w encrypted partition when it is mount ad read-only? From: s m Cc: freebsd-questions Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.17 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Feb 2014 05:32:37 -0000 thank you guys for your completed answers. "u" flag solve my problem:) thank you so much Sam On Sun, Feb 16, 2014 at 1:42 AM, wrote: > TL;DR: the sync command shouldn't be needed. The mount command should > be enough. > > On Thu, Feb 13, 2014 at 01:28:36PM +0100, Polytropon wrote: > > THis _should_ work with GELI encrypted partitions too, even > > though I haven't tested it. Note that reverting back to r/o > > could be delayed when writes are still pending; calling "sync" > > should issue all buffers to be written. In worst case, -f can > > Well, almost. > > The 'sync' command uses the sync system call, and that system call > _schedules_ > blocks for writing but does _not_ wait for them to be written. > > Traditionally, at least. Before the 'clean bit' was added to the filesystem > (about 20 years ago) the traditional way to stop a system was the command > sequence: > sync ; sync ; sync ; halt > > (Well, ok, that's how I was taught.) > > I assume the sync command still works the same way. I'm backlevel and > still running 8.2, but the sync system call man page still says this: > > BUGS > The sync() system call may return before the buffers are completely > flushed. > > Personally, I hope that the attempt to change the filesystem to read-only > would be hint enough that all buffers need to be flushed right now. I > also hope the mount command does not return until the job is done. If it > does then a bug report should probably be filed. > -- > "A method for inducing cats to exercise consists of directing a beam of > invisible light produced by a hand-held laser apparatus onto the floor ... > in the vicinity of the cat, then moving the laser ... in an irregular way > fascinating to cats,..." -- US patent 5443036, "Method of exercising a cat" >