How Retention Works with NovaBACKUP Cloud: Incremental Forever and Data Pruning

Background: What Is Incremental Forever?

NovaBACKUP Cloud uses an Incremental Forever backup methodology. In this approach, an initial full backup is taken once, and all subsequent backups capture only the blocks that have changed since the last run. There are no recurring full backups.

This is different from a traditional full + incremental schedule, where a new full backup is created on a regular cycle (weekly, monthly, etc.) and old backup sets can be deleted wholesale when they age out.

How Retention Is Enforced

In an Incremental Forever backup set, retention is enforced through a process called pruning, not simple deletion.

Here is what that means in practice:

Backup data is stored in timestamped folders within your cloud storage. Each folder name contains .dat as part of its naming convention and represents a point in time within your backup history.
Inside each timestamped folder are encrypted and compressed files that correspond to individual files and partial file blocks from the source machine.
NovaBACKUP tracks which of these stored blocks and files fall within your defined retention window.
As individual blocks and files age beyond the retention threshold, the backup engine removes the corresponding objects during a consolidation pass.
This process is gradual. It runs in the background according to the backup schedule and the volume of stored data.

Important: Older restore points will remain visible in the backup catalog even after some of their data has been pruned. A restore point only disappears from the list once all of the objects within its timestamped folder have aged out of retention and been removed through consolidation.

Why You May Still See Old Backups After Setting a Retention Policy

If you recently configured a retention policy or imported an existing backup history, you may notice that restore points older than your retention window are still visible. This is expected behavior for several reasons:

The pruning/consolidation process has not yet run enough cycles to remove all aged-out data.
Imported backup histories bring their full history with them. The retention engine will begin pruning from the import point forward.
Restore points that share data with more recent backups cannot be fully removed until consolidation determines that no active restore points depend on those blocks.

Over time, as backups continue to run and consolidation passes complete, storage consumption will stabilize and older restore points will disappear.

What to Expect Over Time

Phase	What You See
Shortly after initial setup or import	All restore points visible; storage may appear higher than expected
After several backup cycles	Older restore points begin disappearing as pruning runs
Steady state	Storage stabilizes; only restore points within the retention window remain

When to Open a Support Ticket

If storage continues to grow significantly beyond what your retention policy should allow after several weeks and multiple backup cycles, that may indicate an issue with the consolidation process. In that case, please open a support ticket so we can review your backup history.

Best Practices

Set your retention policy before taking the initial full backup when possible. This gives the engine the clearest starting point.
Avoid changing retention policies frequently on an active backup set, as this can slow down consolidation.
Monitor storage usage in your cloud bucket over a 2 to 4 week period after configuring retention to confirm the trend is stable or declining.
If you import an existing backup history, expect a consolidation period before retention is fully reflected in storage usage.