Re: BTRFS Broken, Help

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

On 2024/1/5 02:14, Isaac Chang wrote:
> My Server blipped and upon reboot, the Cache Drives (pool of 2 devices
> RAID 0) are now unmountable. I can mount the lead disk in CLI and peruse
> the files but if I use MV or CP or rsync, I get Input/Output errors.
> BTRFS restore also yields Input/Output errors.
> Using the instructions here as this is an UNRAID server:
> https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/#comment-543490 <https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/#comment-543490>
>
>   root@Tower:/# uname -a
> Linux Tower 6.1.64-Unraid #1 SMP PREEMPT_DYNAMIC Wed Nov 29 12:48:16 PST
> 2023 x86_64 Intel(R) Xeon(R) CPU           L5638  @ 2.00GHz GenuineIntel
> GNU/Linux
> root@Tower:/# btrfs --version
> btrfs-progs v6.3.3
> root@Tower:/# btrfs fi df /temp
> Data, RAID0: total=887.40GiB, used=606.95GiB
> System, RAID1: total=32.00MiB, used=96.00KiB
> Metadata, RAID1: total=3.00GiB, used=1.05GiB
> GlobalReserve, single: total=117.83MiB, used=0.00B
> root@Tower:/# btrfs fi show
> Label: none  uuid: 15b03357-29bc-43b0-bfbb-b306a3611d8f
>          Total devices 1 FS bytes used 408.00KiB
>          devid    1 size 1.00GiB used 126.38MiB path /dev/loop2
>
> Label: none  uuid: b53ef962-5a9b-4c35-98a3-33ff77ebaac5
>          Total devices 2 FS bytes used 608.00GiB
>          devid    1 size 465.76GiB used 446.73GiB path /dev/sdg1
>          devid    2 size 0 used 0 path  MISSING

One of your disk is missing.

In fact that disk (ata5) is dead:

[ 7517.440956] ata5.00: exception Emask 0x0 SAct 0x40000fff SErr 0x0
action 0x0
[ 7517.440967] ata5.00: irq_stat 0x40000001
[ 7517.440972] ata5.00: failed command: READ FPDMA QUEUED
[ 7517.440975] ata5.00: cmd 60/08:00:50:3f:61/04:00:38:00:00/40 tag 0
ncq dma 528384 in
                         res 41/04:b8:f9:3d:61/00:01:38:00:00/00 Emask
0x1 (device error)
[ 7517.440985] ata5.00: status: { DRDY ERR }
[ 7517.440988] ata5.00: error: { ABRT }

Which failed to do a basic read.

You can try mount with "ro,rescue=all,degraded" to salvage whatever you
still have.

Thanks,
Qu
>
> ERROR: superblock checksum mismatch
> ERROR: cannot scan /dev/sdf1: Input/output error
>
>
> Attached is the dmesg output.
> Please let me know what I can do.
>
> Thank you!
>
> Isaac Chang