From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-31.italiaonline.it ([212.48.25.159]:53057 "EHLO libero.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751012AbbEDVZW (ORCPT ); Mon, 4 May 2015 17:25:22 -0400 Message-ID: <5547E3BF.4090901@inwind.it> Date: Mon, 04 May 2015 23:25:19 +0200 From: Goffredo Baroncelli Reply-To: kreijack@inwind.it MIME-Version: 1.0 To: TheJay , linux-btrfs@vger.kernel.org Subject: Re: [REQ] Help to gain access to btrfsraid6 pool that won't mount References: In-Reply-To: Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 2015-05-04 17:44, TheJay wrote: > $ uname -a > Linux thejay-srv03 4.0.0-040000-generic #201504121935 SMP Sun Apr 12 > 23:36:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux > > $ btrfs --version > btrfs-progs v3.19.1 > > $ sudo btrfs fi show > Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea > Total devices 4 FS bytes used 2.67TiB > devid 1 size 1.36TiB used 1.36TiB path /dev/sdz > devid 3 size 1.36TiB used 1.36TiB path /dev/sdaa > devid 4 size 1.36TiB used 1.36TiB path /dev/sdab > *** Some devices missing > > This pool is a btrfsraid6 pool > > when trying to mount I get: > > $ sudo mount -t btrfs -o recovery,ro /dev/sdaa /mnt/roms03 > mount: wrong fs type, bad option, bad superblock on /dev/sdaa, > missing codepage or helper program, or other error > In some cases useful info is found in syslog - try > dmesg | tail or so > > $ dmesg -T|tail > [Mon May 4 08:35:08 2015] BTRFS info (device sdz): enabling auto recovery > [Mon May 4 08:35:08 2015] BTRFS info (device sdz): disk space caching is > enabled > [Mon May 4 08:35:08 2015] BTRFS: has skinny extents > [Mon May 4 08:35:08 2015] BTRFS: failed to read chunk tree on sdz > [Mon May 4 08:35:08 2015] BTRFS: open_ctree failed > > What could I try to see if I can mount this pool and gain access to the > data? A disk is missing, in this case you should use the "degraded" mount option: mount -o degraded /dev/sdaa /mnt/roms03 > > While I have a backup of the data, next time I may not, and I am trying > to learn how to go about. > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- gpg @keyserver.linux.it: Goffredo Baroncelli Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5