From owner-freebsd-hackers@FreeBSD.ORG Tue Sep 26 01:36:49 2006 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C440816A412 for ; Tue, 26 Sep 2006 01:36:49 +0000 (UTC) (envelope-from soralx@cydem.org) Received: from pd3mo3so.prod.shaw.ca (shawidc-mo1.cg.shawcable.net [24.71.223.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1FB1843D8B for ; Tue, 26 Sep 2006 01:36:38 +0000 (GMT) (envelope-from soralx@cydem.org) Received: from pd3mr2so.prod.shaw.ca (pd3mr2so-qfe3.prod.shaw.ca [10.0.141.178]) by l-daemon (Sun ONE Messaging Server 6.0 HotFix 1.01 (built Mar 15 2004)) with ESMTP id <0J6600JPNF4C8M40@l-daemon> for freebsd-hackers@freebsd.org; Mon, 25 Sep 2006 19:36:12 -0600 (MDT) Received: from pn2ml2so.prod.shaw.ca ([10.0.121.146]) by pd3mr2so.prod.shaw.ca (Sun ONE Messaging Server 6.0 HotFix 1.01 (built Mar 15 2004)) with ESMTP id <0J66002QNF4CSKL0@pd3mr2so.prod.shaw.ca> for freebsd-hackers@freebsd.org; Mon, 25 Sep 2006 19:36:12 -0600 (MDT) Received: from soralx.cydem.org ([24.87.27.3]) by l-daemon (Sun ONE Messaging Server 6.0 HotFix 1.01 (built Mar 15 2004)) with ESMTP id <0J6600M3CF4CO0F0@l-daemon> for freebsd-hackers@freebsd.org; Mon, 25 Sep 2006 19:36:12 -0600 (MDT) Date: Mon, 25 Sep 2006 18:36:11 -0700 From: soralx@cydem.org In-reply-to: <20060925205339.GA2049@megan.kiwi-computer.com> To: freebsd-hackers@freebsd.org, rick-freebsd@kiwi-computer.com Message-id: <200609251836.11581.soralx@cydem.org> MIME-version: 1.0 Content-type: text/plain; charset=iso-8859-1 Content-transfer-encoding: 7bit Content-disposition: inline References: <6.2.0.14.2.20060925123108.03038af0@nano.net> <6.2.0.14.2.20060925142809.0300e3e0@nano.net> <20060925205339.GA2049@megan.kiwi-computer.com> User-Agent: KMail/1.9.1 Cc: tech@nano.net Subject: Re: fsck X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Sep 2006 01:36:49 -0000 > > Maybe I can mount a dirty partition..... I just need the data off it... > Mount it read-only and get the data off it IMMEDIATELY. I wouldn't try > fsck-ing on any disk with even a single read or write error. Fsck will > fail if it can't find a real sector to allocate, and I don't think it deals > well with bad sectors anyway. Point is: don't let it. "dd" the drive > ASAP and cut your losses... also, just beware that the OS may panic when reading a corrupt FS (this happened to me at least once). umount all other slices. in case it panicks, use verbose cp (`cp -v`) to see which files are being copied, note those which cause panic, and skip them i would also suggest to dd the drive's contents, and then and then fool around with it for some time (in order of a week) to get the most data off of it. First, determine the cause of the failure (use smartmontools); if it's electronics, you'll see smth like: SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error [...] # 4 Short offline Completed: electrical failure 90% 13469 127 There's a good chance that the thing might heal itself somewhat (black magic!). One of the ATA drives I'm using now had this failure, and it persisted for a few days while I was subjecting the HDD to various stresses (heat/cold, vibration, intense workout, manufacturer's test program, etc). Then suddenly, after about a week, it started working, and still works! (of course, all the data was long rewritten million times :/) If the cause is a media defect, I don't believe there's any chance of recovering anymore data. If it failed because of a 'mild' head-crash, you'd want to be very careful with the drive, and make a copy ASAP; don't move it around too much. [SorAlx] ridin' VN1500-B2