If you do not want to lose backup data due to a physical failure (for example, when the backup data must be saved for a long time), you need to back up data to a media outside the storage system (for example, in the cloud or an external backup device). Use Thin Image Advanced or ShadowImage to temporarily back up data before you back up data on the media. If you want to reduce the capacity of temporary backup data when you back up data on a media outside the storage system, use Thin Image Advanced instead of ShadowImage.
If you want to be prepared for a physical failure of the P-VOL, use both ShadowImage and Thin Image Advanced.