From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Bell Subject: Re: Data loss on MD RAID5 reshape? Date: Wed, 10 Dec 2008 14:26:16 -0500 Message-ID: <20081210192613.GC8354@newbie.thebellsplace.net> References: <20081205222131.GD8219@newbie.thebellsplace.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <20081205222131.GD8219@newbie.thebellsplace.net> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Anyone have anything to add regarding the email below, before I tear the drives apart and start over? On Fri, Dec 05, 2008 at 05:21:32PM -0500, Bob Bell wrote: >I've experienced apparent data loss, and hoping someone out there can >help rescue my data, or at least tell me what went wrong so that I don't >have a repeat event. I first asked this question on linux-lvm, but the >folks there seemed to think it pertained more to RAID than to LVM. > >I was setting up a new server running Ubuntu's Hardy Heron release. >`uname -a` reports: > Linux sherwood 2.6.24-16-server #1 SMP Thu Apr 10 13:58:00 UTC 2008 i686 > GNU/Linux > >I initially created an md RAID5 device with only two components >(matching 320 GB SATA HDDs). I created a single LVM Physical Volume >using the entirety of that md device (320 GB), and then created several >LVM Logical Volumes for different filesystems (all ext3). This was done >using the Ubuntu installer. After installing I used lvresize to >increase the size of a few of the Logical Volumes. These filesystems >hold data that is not a critical part of the system (mail, music, video, >etc.), but still important to me. > >I then copied data onto one of those filesystems (the original source of >the data is no longer available). I then added a third drive to the md >device, which brought the total to 2 active devices and 1 spare device. >I then grew the number of devices to 3 and waited for the reshape to >finish (increasing the capacity to 640 GB). I bumped the values in >/proc/sys/dev/raid/ so that I wouldn't have to wait as long. > >Now that the reshaping has completed, LVM can't find the physical volume >on that device anymore. I tried rebooting the system, but the problem >remained. Checking /proc/mdstat shows that the md device is up and >healthy. The pvdisplay command only shows my other Physical Volume (for >the IDE drives). I found the pvck command and ran that on the md >device, and it states that there is no LVM label on the device. > >It is my understanding that the steps I outlined should have worked. >I planned to follow them with pvresize, then lvresize, then umount, >resize2fs, and mount again. I've seen this procedure outlined a few >different places, including at >http://gentoo-wiki.info/Resize_LVM2_on_RAID5. > >Did I do something wrong? Is there anyway to rescue my data? If >there's no way of saving the data, I'd at least like to figure out what >happened in the first place. > >Thank you. Your thoughtfulness and help is appreciated. > >-- >Bob Bell >-- >To unsubscribe from this list: send the line "unsubscribe linux-raid" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Bob Bell ------------------------------------------------------------------------- "Linux is like living in a teepee. No Windows, no Gates, Apache in house." -- Usenet signature, author unknown