Azure Backup Full

Question

If i have azure backup with retention daily 90 days, monthly 12 and yearly 3 then as i know azure will do the full backup on first intial, am i right? Let say 1st backup happen on 1st Jan then backup at 02 to the next 90 days is incremental?

How about monthly backup, still incremental or full?

Answer 1

You are correct. In Azure Backup, the initial backup is a full backup, and all subsequent backups (whether they are daily, monthly, or yearly) are incremental backups. Even though Azure Backup only takes incremental data after day one, it uses an internal architecture that makes every recovery point behave like a full backup when you need to restore.

The monthly and yearly retention points do not mean Azure Backup performs a new full backup on those dates. Azure Backup continues to use the underlying incremental backup chain and retains the recovery point selected for monthly or yearly retention for the longer retention period. For example, if January 31 is selected as a monthly recovery point, Azure does not need to create a separate full backup specifically for January 31. That recovery point is retained according to the monthly retention policy. Similarly, a yearly recovery point is retained for the specified three years.

So conceptually, your policy would be: January 1 = initial backup, January 2 onward = incremental backups, while selected daily/monthly/yearly recovery points are retained for their respective retention periods. The important point is that "monthly backup" and "yearly backup" in the retention policy refer to how long selected recovery points are retained, not that Azure performs a separate full backup each month or year.

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hth

Marcin

Answer 2

Yes. For Azure VM backups, the first backup is a full backup and subsequent backups are incremental.

For the scenario described:

• If the first backup runs on 1 Jan, that first recovery point is the full backup.
• The following scheduled backups, including the backups taken over the next 90 days, are incremental backups.

The monthly and yearly retention settings do not cause Azure Backup to take separate full backups. They are retention rules applied to recovery points created by the backup schedule.

Key points:

• A backup policy has two parts: schedule and retention.
• Retention is applied to backup points.
• Monthly and yearly retention simply keep selected recovery points longer.
• Each recovery point behaves like a full point for restore, so restoring an older point does not take more time than restoring a newer point.

So in practice:

• Initial backup = full
• Later scheduled backups = incremental
• Monthly/yearly retained points = still based on those scheduled recovery points, not new full backups

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• Manage recovery points
• Azure Backup architecture and components
• Azure Backup - Frequently asked questions