Cannot read 'backupbundle'

[gmmapowell]

I came to sparsebundlefs in an attempt to read my Mac backup from Linux (my Mac just died, so...).

I am able to mount the drive, which then gives me a directory "catalonia.backupbundle". When I try and mount this using sparsebundlefs, I find that it fails because it has the "wrong extension":

sparsebundlefs: /mnt/catalonia.backupbundle is not a sparse bundle (wrong extension): Invalid argument

It would seem that the expectation is that the bundles will have the extension sparsebundle, but presumably Apple changed this at some point.

[torarnv]

Is it a directory? What kind of files does it contain? What happens if you rename it to have a sparsebundle extension?

[gmmapowell]

Yes, it is a directory. It appears to be exactly the same format as a sparsebundle, with files with names like 'fff'.

I did not try renaming it, because it's a backup and I'm scared of messing with it, but changing the code to accept a '.backupbundle' extension did the trick; I submitted a pull request.

However, it didn't get me very far: when I mount the sparse bundle, it becomes a DMG with a huge size that dmg2img complains is corrupt. 7z gives me this:

7z l /sparse/sparsebundle.dmg 

7-Zip 23.01 (x64) : Copyright (c) 1999-2023 Igor Pavlov : 2023-06-20
 64-bit locale=en_GB.UTF-8 Threads:12 OPEN_MAX:1024

Scanning the drive for archives:
1 file, 3734371818496 bytes (3478 GiB)

Listing archive: /sparse/sparsebundle.dmg

--
Path = /sparse/sparsebundle.dmg
Open WARNING: Cannot open the file as [Dmg] archive
Type = GPT
Physical Size = 3734371818496
ID = 8901B9FD-0A80-4CEF-9A8A-2BD14DBC9368

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
                    .....    209715200    209715200  0.EFI System Partition.img
                    ..... 3734027845632 3734027845632  1.disk image.hfsx
------------------- ----- ------------ ------------  ------------------------
                          3734237560832 3734237560832  2 files

Warnings: 1

And I see dark murmurings on the internet about Guid Partition Tables not being easily readable, so I think I may have to give up and try and find a working Mac to read the backup.

[cluck]

You can loop-mount the dmg to let the OS handle the GPT with losetup --find --show --partscan /sparse/sparsebundle.dmg: this will print the created loop device (e.g. loop3) and create additional devices like /dev/loop3p1 for each partition.

From the output above I guess that your next step would be tmfs /dev/loop3p2 /mnt/restore.

Once you don't need the loop-devices anymore, use losetup --detach /dev/loop3 to unwind the loop.