From owner-freebsd-questions@FreeBSD.ORG Tue Mar 31 11:03:12 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0044E106566B for ; Tue, 31 Mar 2009 11:03:11 +0000 (UTC) (envelope-from utisoft@googlemail.com) Received: from mail-ew0-f171.google.com (mail-ew0-f171.google.com [209.85.219.171]) by mx1.freebsd.org (Postfix) with ESMTP id 5B9848FC08 for ; Tue, 31 Mar 2009 11:03:10 +0000 (UTC) (envelope-from utisoft@googlemail.com) Received: by ewy19 with SMTP id 19so2285158ewy.43 for ; Tue, 31 Mar 2009 04:03:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:reply-to:in-reply-to :references:date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=LFwWwD2QVnxvcTSCu7RCUyQFYaoQu2m9lb1yIloigo8=; b=JAKjfYvrjyjRDptlQJuR52XEEQEj0Eq6iBvfDYEMVgY6qYjwgCsyIzXUUpfOeI8KcK u7S75QRIRt8KbUTiF/KPhS4zUluh//BNL7KiDBkikRXfoV+ULLpxwydxoOJd5Ry1coID w2E0Otr2iasjp+xz59AMeC+6N14e+M6gq2eQc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:reply-to:in-reply-to:references:date:message-id :subject:from:to:content-type:content-transfer-encoding; b=XeYGolcWqsafbA2THitnrYjHoaCBQVNzj2tQbYkhEdmrXKNdWqpuetWKR5KOUYJLV3 Q5q+1Gj0gZO3uw7bwHJQQGMNeVyFTXDP0PP3C07f8UJRE16tZHs7+IBK/NHSkkZJGjfc tOV8/n/bCBRh2k90hSZXu7NVGxBeKLrU5HARg= MIME-Version: 1.0 Received: by 10.210.67.13 with SMTP id p13mr492427eba.35.1238497390284; Tue, 31 Mar 2009 04:03:10 -0700 (PDT) In-Reply-To: <49D1F0BA.7050209@gmail.com> References: <49D1B297.8060307@gmail.com> <20090331080137.31122795@gluon.draftnet> <49D1F0BA.7050209@gmail.com> Date: Tue, 31 Mar 2009 12:03:10 +0100 Message-ID: From: Chris Rees To: FreeBSD Mailing List , Wojciech Puchar , invalid.pointer@gmail.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Subject: Re: Question about forcing fsck at boottime X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: utisoft@gmail.com List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 Mar 2009 11:03:12 -0000 2009/3/31 manish jain : > BTW, a lot of people who posted replies thought I was not aware that a preen > is always executed at startup. When I said I wanted to force an fsck, I > meant 'fsck -fy'. As for background checks, they are - in my opinion - a > real nightmare. Even though I am just a learner on FreeBSD still, I can > assure anyone, putting background_fsck="NO" into your rc.conf is one of the > best things you can do. > > As for the reason why I want to force fsck is that it has now happened 3 > timed that, after a clean and proper shutdown - with no foreign filesystems > mounted, FreeBSD has complained on system restart (twice on a 5.x > distribution I had briefly used and now once on 7.1) that / was not properly > unmounted. Having bgfsck enabled is like inviting a dragon to dinner when > this happens. > Sorry, but I have to disagree. The filesystem that FreeBSD uses (UFS to some, FFS to others) has a feature known as 'snapshots', something alien to people in the Linux world. What this means, is that one can take a 'snapshot' of a drive's state (somewhat like a versioning tag), and mount, dump, OR fsck it. The point of a background fsck is that the SNAPSHOT is fsck'd, and only if there is a problem (which there usually isn't, due to soft-updates meaning that data are rarely lost on power loss) does fsck require write access to the volume in question. This is also why you can dump a live filesystem in FreeBSD. Just to reiterate something said a thousand times, there is NOTHING WRONG with background fscks, and just because something doesn't work well for GNU/Linux doesn't mean it doesn't work with FreeBSD. There are many differences, after all. Chris -- A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?