For using Backblaze B2 as a special remote, there are currently three choices:

  • Using rclone
    (Actively maintained)

  • Backblaze B2 supports supports the same API as Amazon S3, so git-annex's built-in S3 special remote can be used with it.

    However, it needs S3 version 4 signatures, which are only supported by git-annex 8.20200508 and newer.

    Here is how to set up the special remote:

      export AWS_ACCESS_KEY_ID=$appKeyId
  export AWS_SECRET_ACCESS_KEY=$appKeySecret
  git annex initremote backblaze type=S3 signature=v4 host=$endpoint bucket=$bucketname protocol=https encryption=$encryption

    Remember to replace:

    • $appKeyId and $appKeySecret with the values displayed by B2 when you created an "Application Key".
    • $endpoint with the B2 endpoint to which your account has an affinity.
      • An easy way to find the correct value is to create a temporary bucket in the service's web UI, and then use the "endpoint" field displayed for that bucket (before deleting the temporary bucket!).
    • $bucketname with the name of the bucket you wish to use
      • This is not the opaque B2 "Bucket ID".
    • $encryption with the encryption setting you want git-annex to apply to the files it stores in the bucket.
      • This is unrelated to the B2 server-side bucket encryption setting.

    If a bucket with the specified name does not already exist then git-annex will attempt to create it. If the access key provided does not permit bucket creation then the initremote command will fail. The bucket will be created in the unchangeable region that the access key's account is pinned to, with infinite versioning enabled and server-side encryption disabled. Given that you're probably using some form of git-annex encryption, and that files with server-side encryption enabled are not included in a server-side bucket-level snapshot, you may wish to leave the server-side encryption disabled.

  • A dedicated special remote, https://github.com/encryptio/git-annex-remote-b2
    (Last updated 2016)

At this time it's not clear which is better, so if you find one works better than the other, please comment below.