This is really the best solution to handle a *.vma outside of ProxMox.

But typically we face with compressed *.vma.gz format, so we have to write a BIG file twice:
*.vma.gz --> *.vma
*.vma --> *.raw

Actually we need a triple free disk space (vma.gz + vma + raw) at a time.

It would be perfect if the script has the ability to use stdin as input (as origin vma has), so we can use it in such a way:

zcat big.vma.gz | vma.py - /tmp/big-vma-extracted

Unfortunately named pipe doesn't work:

$ mkfifo blackhole
$ zcat big.vma.gz > blackhole &
$ vma.py blackhole /tmp/big-vma-extracted

[1]  + 237676 broken pipe  zcat big.vma.gz > blackhole
Traceback (most recent call last):
  File "vma.py", line 357, in <module>
    sys.exit(main())
  File "vma.py", line 352, in main
    extract(fo, args)
  File "vma.py", line 239, in extract
    fo.seek(0, os.SEEK_END)
io.UnsupportedOperation: File or stream is not seekable.

Thank you for your work!

hiya, thanks for this, i get this error

OS: windows 11 | Python 3.10

c:\temp>vma.py blueiris.vma c:\temp\blueiris
Traceback (most recent call last):
File "C:\temp\vma.py", line 357, in
sys.exit(main())
File "C:\temp\vma.py", line 352, in main
extract(fo, args)
File "C:\temp\vma.py", line 243, in extract
vma_header = VmaHeader(fo, args.skip_hash)
File "C:\temp\vma.py", line 14, in init
assert magic == b'VMA\0'
AssertionError

Sorry to abuse the issue system, but I saw no other way to express my gratitude for you creating this vma-extractor. I wish Promox offered the option to backup to a true raw file, and not this VMA obfuscation. I don't understand the reason for VMA even existing unless it is to deter migration to non-proxmox alternatives. This is not the type of behavior I'd expect from an open source project. Perhaps I'm completely wrong, and there are other legitimate reasons for VMA's existence, but no one yet has offered a reason I'd consider legitimate. Feel free too disabuse my speculation.

I posted my concern here:
https://forum.proxmox.com/threads/vma-archive-restore-outside-of-proxmox.14226/post-474023

Hey man,
i want to say thank you so much for this.

I was in Big Trouble for Data-Losses and only got a .vma snapshot as Backup.
With your stuff i got my latest update back and dont lost a wekk of work.

Keep up and thanks again

gremlin@gremlin-VirtualBox:~/Загрузки/vma-extractor-master$ ./vma.py
usage: vma.py [-h] [-v] [-f] [--skip-hash] filename destination
vma.py: error: the following arguments are required: filename, destination

gremlin@gremlin-VirtualBox:~/Загрузки/vma-extractor-master$ ./vma.py /media/sf_DISK_H/vzdump-qemu-101-2023_01_12-16_22_49.vma /media/sf_DISK_D/raw
Error! Destination path exists!

gremlin@gremlin-VirtualBox:~/Загрузки/vma-extractor-master$ ./vma.py /media/sf_DISK_H/vzdump-qemu-101-2023_01_12-16_22_49.vma /media/sf_DISK_D/raw/
Error! Destination path exists!

gremlin@gremlin-VirtualBox:~/Загрузки/vma-extractor-master$ sudo ./vma.py /media/sf_DISK_H/vzdump-qemu-101-2023_01_12-16_22_49.vma /media/sf_DISK_D/raw
[sudo] пароль для gremlin:
Error! Destination path exists!

gremlin@gremlin-VirtualBox:~/Загрузки/vma-extractor-master$ nano /media/sf_DISK_D/raw/1.txt

Please help.