Before you create a synthetic backup, review the following information:
In a policy that contains a synthetic backup, if an encryption key is used, all of the associated templates must use the same encryption key. The encryption key should not be changed after the policy has been created. The encryption key that is selected in the associated templates is automatically applied to the synthetic backup template.
In a policy that contains a synthetic backup, backup templates that create incremental backup jobs must have backup-to-disk folders as destination devices. Before you can save a policy that contains the synthetic backup templates, you must have a backup-to-disk folder that you can select as the destination device for the required incremental backup jobs.
The option Collect additional information for synthetic backup and for true image restore must be selected for backup templates for incremental and full backup jobs created for synthetic backup. This option is on the General page of the Backup Job Template properties.
If the baseline backup job was written to tape, and if you also want to write the synthetic backup job to tape, two tape drives are required: one to mount the source job on (the baseline backup) and one to mount the destination job on (the synthetic backup job).
Following are limitations when running synthetic backup:
If the Central Admin Server Option is installed, the synthetic backup job template and any associated full and incremental job templates must be run on destination devices that can all be accessed by the media server that runs the synthetic backup job.