Veritas NetBackup™ for Microsoft SQL Server Administrator's Guide

You can schedule a backup in one of the following ways:

• Frequency

  Frequency specifies the period of time that can elapse until the next backup operation begins on this schedule. For example, assume that the frequency is 7 days and a successful backup occurs on Wednesday. The next full backup does not occur until the following Wednesday. Typically, incremental backups have a shorter frequency than full backups.

  The frequency can be hours, days, or weeks. For transaction log backups, the frequency can also be minutes.

• Calendar

  The Calendar option lets you schedule the backup operations that are based on specific dates, recurring week days, or recurring days of the month.

The type of schedule you select affects the retention period as follows:

• Frequency-based scheduling

  Set a retention period that is longer than the frequency setting for the schedule. For example, if the frequency setting is set to one week, set the retention period to be more than one week. The NetBackup scheduler compares the latest record of the backup schedule to the frequency of that backup schedule. This comparison determines whether a backup is due. So if you set the retention period to expire the record too early, the scheduled backup frequency is unpredictable. However, if you set the retention period to be longer than necessary, the NetBackup catalog accumulates unnecessary records.

  When NetBackup expires a backup image it does not notify SQL Server. Use SQL Server to periodically delete expired backup sets from the SQL Server repository.

• Calendar-based scheduling

  The retention period setting is not significant for calendar-based scheduling.