From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 5 Jan 2001 08:26:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 5 Jan 2001 08:25:52 -0500 Received: from zeus.kernel.org ([209.10.41.242]:2308 "EHLO zeus.kernel.org") by vger.kernel.org with ESMTP id ; Fri, 5 Jan 2001 08:25:46 -0500 Date: Fri, 5 Jan 2001 13:22:28 +0000 From: "Stephen C. Tweedie" To: Alan Cox Cc: Andreas Dilger , Daniel Phillips , "Stephen C. Tweedie" , linux-kernel@vger.kernel.org Subject: Re: Journaling: Surviving or allowing unclean shutdown? Message-ID: <20010105132228.Y1290@redhat.com> In-Reply-To: <200101050800.f0580He12396@webber.adilger.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: ; from alan@lxorguk.ukuu.org.uk on Fri, Jan 05, 2001 at 12:46:19PM +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Fri, Jan 05, 2001 at 12:46:19PM +0000, Alan Cox wrote: > > recovery. Because the ext3 journal is just a series of data blocks to > > be copied into the filesystem (rather than "actions" to be done), it > > doesn't matter how many times it is done. The recovery flags are not > > reset until after the journal replay is completed. > > Which means an ext3 volume cannot be recovered on a hard disk error. Depends on the error. If the disk has gone hard-readonly, then we need to recover in core, and that's something which is not yet implemented but is a known todo item. Otherwise, it's not worse than an error on ext2: you don't have a guaranteed safe state to return to so you fall back to recovering what you can from the journal and then running an e2fsck pass. e2fsck groks the journal already. And yes, a badly faulty drive can mess this up, but it can mess it for ext2 just as badly. Cheers, Stephen - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/