Snapshots are zip files created from downloading files stored in a B2 bucket. Snapshots are currently only available through the Backblaze website from the Browse Files page and/or the Buckets page. A snapshot is a convenient way to download many files at once at a single point in time. When a snapshot is created, a B2 proprietary bucket is created to store the user’s snapshots in. The b2 proprietary snapshot bucket has the prefix “b2-snapshot-”. This bucket cannot be deleted or modified by the user. Users can, however, download snapshots via the command line tool from the snapshot bucket. If a user wishes to disable B2 or delete their account, all the snapshots they have created must be removed from the snapshot bucket first.
Cost to Create
The maximum size for a single snapshot is 10T. When creating a snapshot using the Backblaze UI, users will not be charged for any B2 transactions involved in creating the snapshot, nor any processing time on our servers. Users will only be charged for the snapshot’s storage once it is uploaded to their snapshot bucket. For B2 storage costs see here.
Estimated Processing Time
Based one our statistics, users can expect snapshots to take approximately 1 minute/GB. This performance varies with snapshots with many small files (> 100,000) or large snapshots with very few files taking longer. At 1min/GB, very large snapshots can take several days to run. Users should also be aware that Backblaze has a regularly scheduled maintenance period each Thursday at 2pm PT during which servers are taken down for maintenance. Snapshots in progress during this maintenance period will be stopped and then will be restarted once the servers are back up. This can add several hours of additional time to the snapshot’s normal processing especially for larger snapshots.
Snapshot Candidate List
The candidate list file for snapshots is determined at the time the snapshot is submitted. If files are deleted from b2 after the snapshot is submitted, while the snapshot is running, it will be noted in the snapshot’s error log up to 50 deleted files. It is up to the user to determine if the snapshot is valid or should be re-created. During the snapshot creation do not delete any of the source B2 files until the snapshot has completed. This is to make certain the snapshot is viable.
By default b2 hidden files (action=”hide”) will not be included in the snapshot. If all the files in a bucket are “hidden”, then the snapshots will display ERROR in the status because there are 0 files to download. There is a checkbox on the submit snapshot modal, which when checked will include all hidden files in the snapshot.