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 0375AC07E9D for ; Sat, 24 Sep 2022 20:08:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233693AbiIXUIl (ORCPT ); Sat, 24 Sep 2022 16:08:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229669AbiIXUIk (ORCPT ); Sat, 24 Sep 2022 16:08:40 -0400 X-Greylist: delayed 583 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Sat, 24 Sep 2022 13:08:39 PDT Received: from lazarescu.org (lazarescu.org [66.23.245.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4321E3ED5F for ; Sat, 24 Sep 2022 13:08:39 -0700 (PDT) Received: from lazarescu.org (93-51-19-110.ip299.fastwebnet.it [93.51.19.110]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lazarescu.org (Postfix) with ESMTPSA id 8E402622B7 for ; Sat, 24 Sep 2022 21:58:55 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 lazarescu.org 8E402622B7 Date: Sat, 24 Sep 2022 21:58:53 +0200 From: Mihai Lazarescu To: linux-btrfs@vger.kernel.org Subject: Re: Recovering suddenly corrupt Btrfs partition? Message-ID: Mail-Followup-To: linux-btrfs@vger.kernel.org References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/2.2.7 (2022-08-07) Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Thursday, September 22, 2022 at 22:16:33 -0700, Daniel Trescott wrote: > If anyone could please advise me on how to get the partition into a > usable read-only state, I'd be extremely grateful. Thank you! > [ 8613.636194] BTRFS error (device sda3): parent transid verify failed > on 66931867648 wanted 541837 found 541832 Important disclaimer: I'm only a user, not developer. I just share my own experience, without any deeper knowledge of BTRFS. "parent transid verify failed" is what I got (then I discovered that the disk also had bad sectors). First think first, I strongly recommend you to do a byte-by-byte copy (image) of the full faulty disk. You can use dd or, if you have bad or unreliable sectors, ddrescue is doing a much better job (can install it with dnf). In my case I could not mount the disk, not even with the second or third superblock copy. So I used btrfs-find-root /dev/... to discover potential root candidates, then I used btrfs restore -m -S -i -t /dev/... 2>&1 | grep -v '^trying another mirror$' | tee btrfs-restore.log with the highest that works. My BTRFS FS was plain (no snapshots, etc.). Here are some additional details: https://btrfs.wiki.kernel.org/index.php/Restore Hope this helps. Mihai