Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756575AbdCWVCS (ORCPT ); Thu, 23 Mar 2017 17:02:18 -0400 Received: from caffeine.csclub.uwaterloo.ca ([129.97.134.17]:45598 "EHLO caffeine.csclub.uwaterloo.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752548AbdCWVCR (ORCPT ); Thu, 23 Mar 2017 17:02:17 -0400 Date: Thu, 23 Mar 2017 17:01:33 -0400 To: Stephen Mueller Cc: linux-kernel@vger.kernel.org Subject: Re: RAID array is gone, please help Message-ID: <20170323210133.GP14186@csclub.uwaterloo.ca> References: <20170323173721.GA14188@csclub.uwaterloo.ca> <87d1da5c-a39b-fd41-62a7-640b0eea5501@mueller.org> <20170323192726.GM14186@csclub.uwaterloo.ca> <9dcb25dc-52f3-f831-6115-6a7feb07de1c@mueller.org> <20170323195903.GO14186@csclub.uwaterloo.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 747 Lines: 20 On Thu, Mar 23, 2017 at 09:09:39PM +0100, Stephen Mueller wrote: > OK, I used gdisk to remove the GPT and MBR from each disk. > mdadm --assemble still doesn't work... says it can't find the > superblock. The mdadm --examine commands also say that no > superblock is detected. Yes the GPT overwrite the superblock. The GPT uses the first 17KB of the disk, and the superblock was at 4KB from the start. > I guess I'll go ahead with --create... At least given the data should start at 1MB from the start, it should not have been overwritten. I do always like disk images before I try anything like that. I am never quite sure what create will do although it will likely do the right thing at least if you get the order right. -- Len Sorensen