Re: btrfs check --repair is clean, but mount fails

[Marc MERLIN <marc@merlins.org>]

On Sun, Feb 28, 2016 at 09:44:36AM +0800, Anand Jain wrote:
> If you have a choice pls add, 'btrfs fi show -d' as well for the outputs
> to be taken at the time of boot just before system's 'btrfs dev scan',
 
Ok, I had to reboot anyway, so here's the state when it's bad:

gargamel:~# btrfs fi show -d
Label: 'btrfs_boot'  uuid: e4c1daa8-9c39-4a59-b0a9-86297d397f3b
        Total devices 1 FS bytes used 43.52GiB
        devid    1 size 79.93GiB used 62.13GiB path /dev/mapper/cryptroot
 
Label: 'dshelf2'  uuid: d4a51178-c1e6-4219-95ab-5c5864695bfd
        Total devices 1 FS bytes used 4.27TiB
        devid    1 size 7.28TiB used 4.44TiB path /dev/mapper/dshelf2
 
Label: 'btrfs_space'  uuid: 01334b81-c0db-4e80-92e4-cac4da867651
        Total devices 2 FS bytes used 1.09TiB
        devid    1 size 836.13GiB used 641.03GiB path /dev/mapper/raid0d1
        devid    2 size 836.13GiB used 641.03GiB path /dev/mapper/raid0d2
 
Label: 'dshelf1'  uuid: 5d0847f8-b243-494a-9e31-0a7c9adbd764
        Total devices 1 FS bytes used 8.88TiB
        devid    1 size 21.83TiB used 8.92TiB path /dev/bcache1

gargamel:~# mount /var/local/space
mount: wrong fs type, bad option, bad superblock on /dev/mapper/raid0d1,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so
[ 3209.752862] BTRFS info (device dm-6): disk space caching is enabled
[ 3209.775418] BTRFS: failed to read the system array on dm-6
[ 3209.807673] BTRFS: open_ctree failed

blkid shows:
/dev/mapper/raid0d1: LABEL="btrfs_space" UUID="01334b81-c0db-4e80-92e4-cac4da867651" UUID_SUB="a87c0954-e0d5-4cdb-acb9-05ed290c16df" TYPE="btrfs" 
/dev/mapper/raid0d2: LABEL="btrfs_space" UUID="01334b81-c0db-4e80-92e4-cac4da867651" UUID_SUB="b4ea90fa-4262-489a-830d-3bd4e7518ff2" TYPE="btrfs" 

but mount fails.

And then:
gargamel:~# btrfs dev scan
Scanning for Btrfs filesystems
gargamel:~# mount /var/local/space
gargamel:~# 

Does this make any sense to you?

Thanks,
Marc
-- 
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Microsoft is to operating systems ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/                         | PGP 1024R/763BE901