Backup Conversion Settings for the SQL Server Agent

Backup conversion settings provide a mechanism for converting one backup type to another backup type if certain conditions are satisfied. If the condition is met, the action or conversion is performed. You can use the backup conversion settings to convert backup type either for default and database subclients or for file and filegroup subclients.

The conversion settings ensure that SQL data is backed up regardless of the circumstances that may cause a backup failure.

Subclient Type

Conversion Type

Conditions for Conversion

Benefits of Conversion


Default and database subclients

Log backup to differential backup

Database recovery model is set to simple.

Simple recovery model does not support log backups. Converting log backup to differential backup ensures that both logs and data are backed up. The backed up data is later used to restore logs and data.


Default and database subclients

Differential backup to full backup

Previous full backup was performed using software other than Commvault.

For the first time users of Commvault, starting with a full backup operation ensures complete data protection. Full backup of data also acts as a baseline for future backups and restores.


  • Default and database subclients
  • File and filegroup subclients


All backups to full backup

  • You are running your first backup by using the Commvault software.
  • Time stamp on the new database is more recent than the last backup performed.
  • Last restore performed was a point-in-time or a transaction mark restore.
  • Any system database (master, model or msdb) was restored after the last backup.
  • Subclient content is modified.

Converting to full backups ensures that you have backed up the latest state of each database or each file and filegroup.

In case of a system database, a full backup ensures that the restored databases are backed up at the most recent point-in-time.


If you do not want to convert your backups under the predefined conditions, you can modify the backup conversion settings.

For information about modifying the configuration, see Enabling the Conversion of Log Backups to Differential Backups for the SQL Server Agent.

Note: In certain circumstances, a non-full backup is automatically converted to a full backup even if the backup conversion settings are disabled. For more information on such scenarios, see Automatic Conversion of Non-Full Backups into Full Backups.

Related Topics

Configuring Backup Conversion Settings for Subclients

Last modified: 10/2/2018 12:04:19 PM