Capacity managed retention type and disk types that support SIS
Capacity managed is selectable for any disk storage unit that is allowed in an SLP. However, for the disk types that support single-instance storage (SIS), Capacity managed functions to various degrees. In order for Capacity managed to operate, NetBackup must know how much space a backup image uses. With SIS enabled on the storage unit, NetBackup cannot know exactly how much space a particular backup image occupies.