Incremental backups act as full backups if the backup policy doesn't contain a full backup schedule.

Problem

If a policy contains only a differential incremental or only a cumulative incremental schedule and no full backup schedule, each incremental backup will run as a full schedule.  This is not client specific but policy specific.

Error Message

No observable error status code.  More data than expected would be backed up.

Cause

The backup policy is the parent level organizational structure for backups.  The full backup schedules and incremental backup schedules are associated with the backup policy.

All differential and incremental backup schedules relate to the full backups performed from within the same policy.

If NetBackup based incremental backups from a client perspective instead of a policy and client perspective one could never have an additional policy backing up any of the same data paths, lest it effect the incremental backup selection.  As such NetBackup was designed so that incremental backups would be based upon the full backups from the same policy and client combination.

Solution

If only an incremental backup schedule is configured in a particular policy then create a full backup schedule inside of the same policy, otherwise those incremental backup schedules would act as full backup, as there isn't a full backup on which to base the incremental backup.

Applies To

This is applicable to both Standard and Windows-NT backup policy types.