From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:27965 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753633AbaLJCnu (ORCPT ); Tue, 9 Dec 2014 21:43:50 -0500 Message-ID: <5487B3FB.4070109@oracle.com> Date: Wed, 10 Dec 2014 10:46:19 +0800 From: Anand Jain MIME-Version: 1.0 To: Florian Uekermann CC: linux-btrfs@vger.kernel.org Subject: Re: Device only missing if unmounted References: <708100218.650154.1418123709778.JavaMail.open-xchange@omgreatgod.store> In-Reply-To: <708100218.650154.1418123709778.JavaMail.open-xchange@omgreatgod.store> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 09/12/2014 19:15, Florian Uekermann wrote: > I am using a few disks in Raid1 mode. This is the output of various > commands in unmounted state. > > root@oot:/# uname -a > Linux oot 3.18.0-rc5+ #1 SMP Sun Nov 23 18:01:56 CET 2014 x86_64 GNU/Linux > root@oot:/# btrfs --version > Btrfs v3.17 > root@oot:/# btrfs fi show > Label: none uuid: be2b3499-7452-4b91-b664-4ec4d7ff62b9 > Total devices 3 FS bytes used 149.68GiB > devid 2 size 465.76GiB used 151.03GiB path /dev/sdb > devid 3 size 465.76GiB used 151.03GiB path /dev/sda > devid 4 size 92.26GiB used 0.00B path /dev/sdc4 > > Btrfs v3.17 > root@oot:/# btrfs fi df /srv/storage/ > Data, RAID1: total=150.00GiB, used=149.40GiB > System, RAID1: total=32.00MiB, used=48.00KiB > Metadata, RAID1: total=1.00GiB, used=287.42MiB > GlobalReserve, single: total=96.00MiB, used=0.00B > > I stripped a few lines from the output of btrfs fi show, which > describe other filesystems. > If I unmount the devices in question, I get the following > output (note that missing devices are reported now): > > root@oot:/# btrfs fi show > Label: none uuid: be2b3499-7452-4b91-b664-4ec4d7ff62b9 > Total devices 4 FS bytes used 149.68GiB > devid 2 size 465.76GiB used 151.03GiB path /dev/sdb > devid 3 size 465.76GiB used 151.03GiB path /dev/sda > devid 4 size 92.26GiB used 0.00B path /dev/sdc4 > *** Some devices missing > > Btrfs v3.17 > > I got into this state by removing a device from the array formatting it > and then adding it again (some time ago, I can't remember the exact > sequence of commands) above you mention both btrfs fi show outputs in unmounted only. It depends on the disk that is read first, you could read super block using btrfs-show-super and check if num_device. > The discrepancy in output between mounted and unmounted state is not > a problem in itself for me, but this issue seems to interrupt systemds > boot sequence, which only continues successfully if I mount the array manually. > The array is not degraded, I just removed a drive (via btrfs delete I think). It may fail if you are mounting more than one subvol during boot and if you don't have this patch. commit 0f23ae74f589304bf33233f85737f4fd368549eb Author: Chris Mason Date: Thu Sep 18 07:49:05 2014 -0700 Revert "Btrfs: device_list_add() should not update list when mounted" This reverts commit b96de000bc8bc9688b3a2abea4332bd57648a49f. > If I try to remove the "missing devices" with the btrfs tool the following > happens: > > btrfs dev del missing /srv/storage > ERROR: error removing the device 'missing' - no missing devices found to remove that means you don't see missing when mounted. if you don't see missing when mounted then no need to run delete missing. ? > btrfs balance start /srv/storage/ does not solve the issue. > -- > 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 >