From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaya Potter Subject: Re: recovering from raid5 corruption Date: Sun, 29 Apr 2012 19:51:04 -0400 Message-ID: <4F9DD3E8.7050701@gmail.com> References: <4F9DC2E5.1090509@gmail.com> <20120430085257.65d19c20@notabene.brown> <4F9DCEC6.1050109@gmail.com> <20120430094546.4702be0a@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120430094546.4702be0a@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On 04/29/2012 07:45 PM, NeilBrown wrote: > On Sun, 29 Apr 2012 19:29:10 -0400 Shaya Potter wrote: > >> On 04/29/2012 06:52 PM, NeilBrown wrote: >>> >>> You've written a new superblock 4K in to each device, where previously here >>> was something. So you have probably corrupted something though we cannot >>> easily tell what. >>> >>> Retry your experiment with --metadata=0.90. Hopefully one of those >>> combinations will work better. If it does, make a backup of the data you >>> want to keep, then I would suggest rebuilding the array from scratch. >> >> ok, thanks, that was a huge help. >> >> I have it setup correctly now (obvious due to the fact that I can read >> the lvm configuration without any gibberish when ordered correctly). > > I should add that this only proves that you have the first device correct, > the rest may be wrong. > You need to activate the LVM, then look at the filesystem and see if it is > consistent before you can be sure that all devices are in the correct > position. true, but that also brings my permutations down to 2 (based on my assumption that disks in slot 2 (missing), 3 (uncorrupted), are correct. so hopefully restoring lvm doesn't mess up any other data (though probably have to make sure that ext3 doesn't do any journal reading/writing in an attempt to mount to see if setup correctly as well).