Is BTRFS recovery possible?

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1

I have a VDI file that has a corrupted BTRFS inside. I’ve made a copy of the VDI file and am attempting recovery in a new VM. I’ve reviewed many articles before coming here. I’m asking, a possible duplicate question, to see if there is any new information on this file system that could allow me to recover it.

The current VM is using Fedora 35. Prior to updating, btrfs check --repair /dev/sdb2 produced a lot of enteries. After running dnf update it only reports error [4 0]

>mount -t btrfs -o ro,rescue=usebackuproot /dev/sdb2 /data2
wrong fs type, bad option, bad superblock on /dev/sdb2, missing codepage or helper programm or other error.

>btrfs fi show
label: fedora_localhost-live uuidL: 044dffdd-5125-4450-af0f-8605a0f12f25
total devices 1 fs bytes used 10gb
devid 1 size 31gb used 13gb path /dev/sdb2

>btrfs rescue super-recover /dev/sdb2
all supers are valid, no need to recover

>btrfs check --repair /dev/sdb2
starting repair
opening file system to check ...
parent transid verify failed on 30408704 wanted 339510 found 346008
Ignoring transid failure
error: root [4 0] level 2 does not match 0

>btrfs rescue chuck-recover /dev/sdb2
chuck tree recovery failed

=====

All Devices:
    Device: id = 1, name = /dev/sdb2

Scanning: DONE in dev0                       
DEVICE SCAN RESULT:
Filesystem Information:
    sectorsize: 4096
    nodesize: 16384
    tree root generation: 347376
    chunk root generation: 339510

All Devices:
    Device: id = 1, name = /dev/sdb2

All Block Groups:
    Block Group: start = 1048576, len = 4194304, flag = 2
    Block Group: start = 5242880, len = 8388608, flag = 4
    Block Group: start = 13631488, len = 8388608, flag = 1
    Block Group: start = 22020096, len = 8388608, flag = 22
    Block Group: start = 30408704, len = 268435456, flag = 24
    Block Group: start = 298844160, len = 1073741824, flag = 1
    Block Group: start = 1372585984, len = 1073741824, flag = 1
    Block Group: start = 2446327808, len = 1073741824, flag = 1
    Block Group: start = 3520069632, len = 1073741824, flag = 1
    Block Group: start = 4593811456, len = 1073741824, flag = 1
    Block Group: start = 5667553280, len = 1073741824, flag = 1
    Block Group: start = 6741295104, len = 268435456, flag = 24
    Block Group: start = 7009730560, len = 1073741824, flag = 1
    Block Group: start = 8083472384, len = 1073741824, flag = 1
    Block Group: start = 9157214208, len = 1073741824, flag = 1
    Block Group: start = 10230956032, len = 1073741824, flag = 1
    Block Group: start = 11304697856, len = 1073741824, flag = 1

All Chunks:
    Chunk: start = 1048576, len = 4194304, type = 2, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 1048576
    Chunk: start = 5242880, len = 8388608, type = 4, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 5242880
    Chunk: start = 13631488, len = 8388608, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 13631488
    Chunk: start = 22020096, len = 8388608, type = 22, num_stripes = 2
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 22020096
        [ 1] Stripe: devid = 1, offset = 30408704
    Chunk: start = 30408704, len = 268435456, type = 24, num_stripes = 2
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 38797312
        [ 1] Stripe: devid = 1, offset = 307232768
    Chunk: start = 298844160, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 575668224
    Chunk: start = 1372585984, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 1649410048
    Chunk: start = 2446327808, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 2723151872
    Chunk: start = 3520069632, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 3796893696
    Chunk: start = 4593811456, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 4870635520
    Chunk: start = 5667553280, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 5944377344
    Chunk: start = 6741295104, len = 268435456, type = 24, num_stripes = 2
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 7018119168
        [ 1] Stripe: devid = 1, offset = 7286554624
    Chunk: start = 7009730560, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 7554990080
    Chunk: start = 8083472384, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 8628731904
    Chunk: start = 9157214208, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 9702473728
    Chunk: start = 10230956032, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 10776215552
    Chunk: start = 11304697856, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 11849957376
    Chunk: start = 12378439680, len = 1073741824, type = 1, num_stripes = 1
        Stripes list:
        [ 0] Stripe: devid = 1, offset = 12923699200

All Device Extents:
    Device extent: devid = 1, start = 1048576, len = 4194304, chunk offset = 1048576
    Device extent: devid = 1, start = 5242880, len = 8388608, chunk offset = 5242880
    Device extent: devid = 1, start = 13631488, len = 8388608, chunk offset = 13631488

CHECK RESULT:
Recoverable Chunks:
  Chunk: start = 1048576, len = 4194304, type = 2, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 1048576
      Block Group: start = 1048576, len = 4194304, flag = 2
      Device extent list:
          [ 0]Device extent: devid = 1, start = 1048576, len = 4194304, chunk offset = 1048576
  Chunk: start = 5242880, len = 8388608, type = 4, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 5242880
      Block Group: start = 5242880, len = 8388608, flag = 4
      Device extent list:
          [ 0]Device extent: devid = 1, start = 5242880, len = 8388608, chunk offset = 5242880
  Chunk: start = 13631488, len = 8388608, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 13631488
      Block Group: start = 13631488, len = 8388608, flag = 1
      Device extent list:
          [ 0]Device extent: devid = 1, start = 13631488, len = 8388608, chunk offset = 13631488
Unrecoverable Chunks:
  Chunk: start = 22020096, len = 8388608, type = 22, num_stripes = 2
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 22020096
      [ 1] Stripe: devid = 1, offset = 30408704
      Block Group: start = 22020096, len = 8388608, flag = 22
      No device extent.
  Chunk: start = 30408704, len = 268435456, type = 24, num_stripes = 2
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 38797312
      [ 1] Stripe: devid = 1, offset = 307232768
      Block Group: start = 30408704, len = 268435456, flag = 24
      No device extent.
  Chunk: start = 298844160, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 575668224
      Block Group: start = 298844160, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 1372585984, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 1649410048
      Block Group: start = 1372585984, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 2446327808, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 2723151872
      Block Group: start = 2446327808, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 3520069632, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 3796893696
      Block Group: start = 3520069632, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 4593811456, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 4870635520
      Block Group: start = 4593811456, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 5667553280, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 5944377344
      Block Group: start = 5667553280, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 6741295104, len = 268435456, type = 24, num_stripes = 2
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 7018119168
      [ 1] Stripe: devid = 1, offset = 7286554624
      Block Group: start = 6741295104, len = 268435456, flag = 24
      No device extent.
  Chunk: start = 7009730560, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 7554990080
      Block Group: start = 7009730560, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 8083472384, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 8628731904
      Block Group: start = 8083472384, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 9157214208, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 9702473728
      Block Group: start = 9157214208, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 10230956032, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 10776215552
      Block Group: start = 10230956032, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 11304697856, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 11849957376
      Block Group: start = 11304697856, len = 1073741824, flag = 1
      No device extent.
  Chunk: start = 12378439680, len = 1073741824, type = 1, num_stripes = 1
      Stripes list:
      [ 0] Stripe: devid = 1, offset = 12923699200
      No block group.
      No device extent.

Total Chunks:       18
  Recoverable:      3
  Unrecoverable:    15

Orphan Block Groups:

Orphan Device Extents:

No mapping for 6948208640-6948225024
Couldn't map the block 6948208640
Couldn't read tree root
open with broken chunk error
Chunk tree recovery failed

=====

GParted 1.3.1

configuration --enable-libparted-dmraid --enable-online-resize

libparted 3.4

========================================
Device: /dev/sda
Model:  ATA VBOX HARDDISK
Serial: 
Sector size:    512
Total sectors:  41943040
 
Heads:  255
Sectors/track:  2
Cylinders:  82241
 
Partition table:    msdos
 
Partition   Type    Start   End Flags   Partition Name  File System Label   Mount Point
/dev/sda1   Primary 2048    2099199 boot        ext4        /boot
/dev/sda2   Primary 2099200 41943039            btrfs   fedora_localhost-live   /, /home

========================================
Device: /dev/sdb
Model:  ATA VBOX HARDDISK
Serial: 
Sector size:    512
Total sectors:  67108864
 
Heads:  255
Sectors/track:  2
Cylinders:  131586
 
Partition table:    msdos
 
Partition   Type    Start   End Flags   Partition Name  File System Label   Mount Point
/dev/sdb1   Primary 2048    2099199 boot        ext4        
/dev/sdb2   Primary 2099200 67108863            btrfs   fedora_localhost-live   

========================================
Device: /dev/sdc
Model:  ATA VBOX HARDDISK
Serial: 
Sector size:    512
Total sectors:  41943040
 
Heads:  255
Sectors/track:  2
Cylinders:  82241
 
Partition table:    none
 
Partition   Type    Start   End Flags   Partition Name  File System Label   Mount Point
/dev/sdc    Unpartitioned   0   41943039            ext4    data    

========================================
Check and repair file system (btrfs) on /dev/sdb2  00:14:33    ( ERROR )
        
calibrate /dev/sdb2  00:00:02    ( SUCCESS )
        
path: /dev/sdb2 (partition)
start: 2099200
end: 67108863
size: 65009664 (31.00 GiB)
check file system on /dev/sdb2 for errors and (if possible) fix them  00:14:31    ( ERROR )
        
btrfs check '/dev/sdb2'  00:14:31    ( ERROR )
        
Opening filesystem to check...
Checking filesystem on /dev/sdb2
UUID: 044dffdd-5125-4450-af0f-8605a0f12f25
found 10820648960 bytes used, error(s) found
total csum bytes: 5961932
total tree bytes: 103399424
total fs tree bytes: 61751296
total extent tree bytes: 31014912
btree space waste bytes: 16456853
file data blocks allocated: 4281233408
referenced 2388201472

Any other suggestions and offline assistance would be helpful.

2

NO

A copy-on-write file system not able to be rolled back or recovered …

It is unfortunately the only FS supported by Fedora & Windows, what a monument of human folly.

3

BTW, if you saw any document with warnings like these, RUN:

–repair
enable the repair mode and attempt to fix problems where possible

NOTE:

There’s a warning and 10 second delay when this option is run without –force to give users a chance to think twice before running repair, the warnings in documentation have shown to be insufficient.

–init-csum-tree
create a new checksum tree and recalculate checksums in all files

WARNING:

Do not blindly use this option to fix checksum mismatch problems.

–init-extent-tree
build the extent tree from scratch

WARNING:

Do not use unless you know what you’re doing.