Deletion of Unfinished Multipart Uploads in BackBlaze (B2) Buckets

Situation

In order to upload large files (100+ MB in size) to BackBlaze B2 storage, it is necessary for the MSP360 Backup software to divide such files into smaller, discrete pieces called “multiparts”, which are later assembled into a final file, once all the multiparts are uploaded successfully.

In some cases, a file could be uploaded incorrectly (think of a single large file and an unstable network connection), so that its upload would have to be restarted from scratch. If such a situation occurs, the older multiparts that were never assembled into a final file would still remain in BackBlaze storage and consume your billed storage space.

Below, we suggest a solution that can help you get rid of unfinished and technically unusable multiparts in BackBlaze.

Solution

Please follow these steps:

1. Install the BackBlaze CLI (command line interface) tool from the B2 official website: https://www.backblaze.com/b2/docs/quick_command_line.html
2. Launch the Windows command prompt console under administrator privileges and navigate to the location of the downloaded “b2.exe” file, then execute it:

3. After the B2 CLI finishes initialization, use the following command to authorize your B2 account (note the customizable command parameters):

b2 authorize-account *[applicationKeyID] [applicationKey]*

4. Once this is done, use this command to remove the unfinished multiparts (note the customizable bucketName argument: the name of the bucket that requires multipart cleaning):

b2 cancel-all-unfinished-large-files *bucketName*

This procedure should purge the unfinished multipart data and reduce ineffective storage consumption in the corresponding B2 bucket.