"Failed to acquire write lock" FUSE

[feboss]

I want backup in a ftp and i mount my ftp with curlftpfs. But i can't init. This is the error i get attic: Error: Failed to acquire write lock on test/config what can i do?

[ThomasWaldmann]

Likely your fs does not support fcntl.lockf (with LOCK_EX to get an exclusive lock).

An idea would be to implement (or reuse) a different way of locking, e.g. directory based. portalocker?

[jasontbradshaw]

I'm getting the same error after running attic init on a repository located on a ZFS file system:

$ attic init test-repository
Initializing repository at "test-repository"
attic: Error: Failed to acquire write lock on test-repository/config

The repository appears to have been created even after the error, but attempting to attic create to it fails with the same error after a moment or two.

I would be happy to implement a directory-based locking mechanism, but pointers on where to start would be appreciated.

[ThomasWaldmann]

@jasontbradshaw that was a locally mounted zfs? which OS precisely?

Just wondering: considering the amount of stuff ZFS does support, it would seem strange it does not support such simple things as fcntl.lockf.

[jasontbradshaw]

The ZFS volume is running on a different machine running FreeNAS 9.3 on my local network, and is mounted using NFSv3. My desktop (on which I was attempting to run attic) runs Arch Linux.

[jasontbradshaw]

Now that you mention it, NFS is probably the issue. However, this doesn't change the general problem that attic (apparently) requires a lock to operate, and can't reliably obtain one on all filesystems.

[ThomasWaldmann]

Ah, NFS, that explains it.

For NFS, maybe running lockd would help?

About the state of locking in general: http://0pointer.de/blog/projects/locking.html

[ThomasWaldmann]

@feboss @jasontbradshaw ^^^ can you try?

[feboss]

i installed borg with pip3. get this:

root@server1:/mnt/ftpB# borg init b
Initializing repository at "b"
Traceback (most recent call last):
  File "/usr/local/lib/python3.4/dist-packages/borg/helpers.py", line 50, in __init__
    fcntl.lockf(self.fd, fcntl.LOCK_EX)
OSError: [Errno 9] Bad file descriptor

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.4/dist-packages/borg/archiver.py", line 857, in main
    exit_code = archiver.run(sys.argv[1:])
  File "/usr/local/lib/python3.4/dist-packages/borg/archiver.py", line 813, in run
    return args.func(args)
  File "/usr/local/lib/python3.4/dist-packages/borg/archiver.py", line 62, in do_init
    repository = self.open_repository(args.repository, create=True, exclusive=True)
  File "/usr/local/lib/python3.4/dist-packages/borg/archiver.py", line 37, in open_repository
    repository = Repository(location.path, create=create, exclusive=exclusive)
  File "/usr/local/lib/python3.4/dist-packages/borg/repository.py", line 59, in __init__
    self.open(path, exclusive)
  File "/usr/local/lib/python3.4/dist-packages/borg/repository.py", line 120, in open
    self.lock = UpgradableLock(os.path.join(path, 'config'), exclusive)
  File "/usr/local/lib/python3.4/dist-packages/borg/helpers.py", line 56, in __init__
    raise self.WriteLockFailed(self.path)
borg.helpers.WriteLockFailed: b/config
borg: Error: Failed to acquire write lock on b/config

[ThomasWaldmann]

I meant the code from git (the new locking code is not on pypi yet).

[jasontbradshaw]

lockd already appears to be running on the FreeNAS box.

After installing attic manually from git (python setup.py install, etc.), I get the exact same error.

[ThomasWaldmann]

I did the changes in borgbackup (a fork of attic): https://github.com/borgbackup/borg

Sorry for the confusion.

BTW, if you test the new code and have feedback for it, please use the issue tracker there.