From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69C15ECAAD4 for ; Wed, 31 Aug 2022 20:37:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229762AbiHaUhu convert rfc822-to-8bit (ORCPT ); Wed, 31 Aug 2022 16:37:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229886AbiHaUht (ORCPT ); Wed, 31 Aug 2022 16:37:49 -0400 Received: from mail.stoffel.org (li1843-175.members.linode.com [172.104.24.175]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AD66E3983 for ; Wed, 31 Aug 2022 13:37:48 -0700 (PDT) Received: from quad.stoffel.org (068-116-170-226.res.spectrum.com [68.116.170.226]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.stoffel.org (Postfix) with ESMTPSA id 429BE229F4; Wed, 31 Aug 2022 16:37:47 -0400 (EDT) Received: by quad.stoffel.org (Postfix, from userid 1000) id 9BAB7A7E3F; Wed, 31 Aug 2022 16:37:46 -0400 (EDT) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Message-ID: <25359.50842.604856.467479@quad.stoffel.home> Date: Wed, 31 Aug 2022 16:37:46 -0400 From: "John Stoffel" To: Peter Sanders Cc: Wols Lists , Eyal Lebedinsky , linux-raid@vger.kernel.org Subject: Re: RAID 6, 6 device array - all devices lost superblock In-Reply-To: References: <70e2ae22-bbba-77a4-c9bc-4c02752f4cb7@youngman.org.uk> <4a414fc6-2666-302f-8d3d-08eb7a2986fc@turmel.org> <25355.47062.897268.3355@quad.stoffel.home> <25355.50871.743993.605394@quad.stoffel.home> <25357.13191.843087.630097@quad.stoffel.home> <1d978f6c-e1cc-e928-efc5-11ff167938b1@eyal.emu.id.au> <8e994200-146e-61ce-bb4a-f7f111f47b10@youngman.org.uk> X-Mailer: VM 8.2.0b under 27.1 (x86_64-pc-linux-gnu) Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org >>>>> "Peter" == Peter Sanders writes: > encountering a puzzling situation. > dmsetup is failing to return. I don't think you need to use dmsetup in your case, but can you post *all* the commands you ran before you got to this point, and the output of cat /proc/mdstat as well? Thinking on this some more, you might need to actually also add: --assume-clean to the 'mdadm create ....' string, since you don't want it to zero the array or anything. Sorry for not remembering this at the time! So if you can, please just start over from scratch, showing the setup of the loop devices, the overlayfs setup, and the building the RAID6 array, along with the cat /proc/mdstat after you do the initial build. John P.S. For those who hated my email citing tool, I pulled it out for now. Only citing with > now. :-) > root@superior:/mnt/backup# dmsetup status > sdg: 0 5860533168 snapshot 16/8388608000 16 > sdf: 0 5860533168 snapshot 16/8388608000 16 > sde: 0 5860533168 snapshot 16/8388608000 16 > sdd: 0 5860533168 snapshot 16/8388608000 16 > sdc: 0 5860533168 snapshot 16/8388608000 16 > sdb: 0 5860533168 snapshot 16/8388608000 16 > dmsetup remove sdg runs for hours. > Canceled it, ran dmsetup ls --tree and find that sdg is not present in the list. > dmsetup status shows: > sdf: 0 5860533168 snapshot 16/8388608000 16 > sde: 0 5860533168 snapshot 16/8388608000 16 > sdd: 0 5860533168 snapshot 16/8388608000 16 > sdc: 0 5860533168 snapshot 16/8388608000 16 > sdb: 0 5860533168 snapshot 16/8388608000 16 > dmsetup ls --tree > root@superior:/mnt/backup# dmsetup ls --tree > sdf (253:3) > ├─ (7:3) > └─ (8:80) > sde (253:1) > ├─ (7:1) > └─ (8:64) > sdd (253:2) > ├─ (7:2) > └─ (8:48) > sdc (253:0) > ├─ (7:0) > └─ (8:32) > sdb (253:5) > ├─ (7:5) > └─ (8:16) > any suggestions? > On Tue, Aug 30, 2022 at 2:03 PM Wols Lists wrote: >> >> On 30/08/2022 14:27, Peter Sanders wrote: >> > >> > And the victory conditions would be a mountable file system that passes a fsck? >> >> Yes. Just make sure you delve through the file system a bit and satisfy >> yourself it looks good, too ... >> >> Cheers, >> Wol