From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from magic.merlins.org ([209.81.13.136]:33608 "EHLO mail1.merlins.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753817AbbFQHRD (ORCPT ); Wed, 17 Jun 2015 03:17:03 -0400 Date: Wed, 17 Jun 2015 00:16:54 -0700 From: Marc MERLIN To: linux-btrfs Message-ID: <20150617071654.GI16468@merlins.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Subject: BTRFS: read error corrected: ino 1 off 226840576 (dev /dev/mapper/dshelf1 sector 459432) Sender: linux-btrfs-owner@vger.kernel.org List-ID: I had a few power offs due to a faulty power supply, and my mdadm raid5 got into fail mode after 2 drives got kicked out since their sequence numbers didn't match due to the abrupt power offs. I brought the swraid5 back up by force assembling it with 4 drives (one was really only a few sequence numbers behind), and it's doing a full parity rebuild on the 5th drive that was farther behind. So I can understand how I may have had a few blocks that are in a bad state. I'm getting a few (not many) of those messages in syslog. BTRFS: read error corrected: ino 1 off 226840576 (dev /dev/mapper/dshelf1 sector 459432) Filesystem looks like this: Label: 'btrfs_pool1' uuid: 6358304a-2234-4243-b02d-4944c9af47d7 Total devices 1 FS bytes used 8.29TiB devid 1 size 14.55TiB used 8.32TiB path /dev/mapper/dshelf1 gargamel:~# btrfs fi df /mnt/btrfs_pool1 Data, single: total=8.29TiB, used=8.28TiB System, DUP: total=8.00MiB, used=920.00KiB System, single: total=4.00MiB, used=0.00B Metadata, DUP: total=14.00GiB, used=10.58GiB Metadata, single: total=8.00MiB, used=0.00B GlobalReserve, single: total=512.00MiB, used=0.00B Kernel 3.19.8. Just to make sure I understand, do those messages in syslog mean that my metadata got corrupted a bit, but because I have 2 copies, btrfs can fix the bad copy by using the good one? Also, if my actual data got corrupted, am I correct that btrfs will detect the checksum failure and give me a different error message of a read error that cannot be corrected? I'll do a scrub later, for now I have to wait 20 hours for the raid rebuild first. Thanks, Marc -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ | PGP 1024R/763BE901