Symantec recommends that you set up a policy with a minimum of a weekly full backup and a daily incremental backup. You can add other templates as needed.
See Best practices for true image restore.
You can also use the Policy Wizard to create a policy for true image restore.
See Creating a policy for true image restore by using the Policy Wizard.
When the Central Admin Server Option (CASO) is installed, Backup Exec ensures that full and incremental backups that have the Collect additional information for synthetic backup and for true image restore option enabled are sent to a device that is accessible by the same media server. If it is not possible to send the full and incremental backups to devices that are accessible by the same media server, the policy cannot be created. You are prompted to change the policy and resubmit it. Additionally, a true image restore operation is delegated to the media server that has access to the device that contains the selected backup set.
More Information
Collecting additional information for synthetic backup and true image restore
Requirements for running true image restore