b2_fuse - FUSE for Backblaze B2

Version: 1.2

Warning this software may contain bugs, be careful of using it with important data.

Please report bugs, use-case issues and feature requests through the Github issue tracker

Basic setup:

Requires YAML and FUSE for python to work (this is not the same as "python-fuse" package).

Install YAML for python as follows:

sudo apt-get install python-yaml

Install FUSE for python as follows:

sudo apt-get install python-pip
sudo pip install fusepy

An example config ("config.yaml"):

accountId: <youraccountid>
applicationKey: <yourapplicationid>
bucketId: <yourbucketid>

Online only copy

This FUSE driver can be used either with a (small) memory backing for current open files or a complete local copy. In order to use the FUSE driver as an interface to the online service B2 (with no local copy) use:

python b2fuse.py <mountpoint>

Usage notes:

• Can be used as a regular filesystem, but should not (high latency)
• Files are cached in memory. If you write or read very large files this may cause issues (you are limited by available ram)
• Neither permissions or timestamps are supported by B2. B2_fuse ignores any requests to set permissions.
• Filesystem contains ".sha1" files, these are undeletable and contain the hash of the file without the postfix. This feature can be disabled by setting variable "enable_hashfiles" to False.
• Having many files in a bucket (multiples of 1000) will drastically increase the startup time/mount time.
• For optimal performance and throughput, you should store a few large files. Small files suffer from latency issues due to the way B2 API is implemented. Large files will allow you to saturate your internet connection.

With local copy

If you wish to try the local copy variant, this requires a folder to store the local replica in addition to the mountpoint you wish to use.

python b2local.py <local_directory> <mountpoint>

Usage notes:

• Threaded uploads and deletions, large files will cause problems as splitting uploads is not yet supported
• Changes will only take effect online after 15+ seconds. This is a timeout in order to handle multiple successive closures and flushing of the same file.
• First synchronization will take a long time, threading for this is not yet implemented.

Application specific notes:

####Using RSync with B2 Fuse

Since there is no support for updating file times or permissions in a bucket, rsync must be told to ignore both when synching folders (sync will be based on checksum meaning files have to be downloaded to compare).

rsync -avzh --no-perms --no-owner --no-group dir1/ dir2/ 

Option "--inplace" may also be useful. RSync creates a temporary file when syncing, this option will make RSync update the file inplace instead (Effectively twice as fast syncing).

####Using unison to synchronize against mounted folder

Again, we ignore permissions as these are not applicable.

unison dir1/ dir2/ -auto  -perms 0  -batch

Using encfs to overlay a locally encrypted filesystem onto the bucket

Install encfs (apt-get install encfs)

encfs <bucket_mountpoint> <encrypted_filesystem>

Known issues:

• Concurrent access from multiple client will lead to inconsistent results
• Small files give low read/write performance (due to high latency)

Future improvements:

• Use bucket name, instead of bucket id
• Command line parameter to enable ".sha1" files

License: MIT license