When a snapshot volume is reattached to its original volume within a shared disk group, there are two choices for resynchronizing the data in the volume:

• Resynchronize the snapshot from the original volume - updates the snapshot with data from the primary volume that has changed since the snapshot was taken. The snapshot is then again ready to be taken for the purposes of backup or decision support. This type of resynchronization is also known as refreshing the snapshot.

• Resynchronize the original volume from the snapshot - updates the original volume with data from the snapshot volume that has changed since the snapshot was taken. This may be necessary to restore the state of a corrupted database or file system, or to implement upgrades to production software, and is usually much quicker than using alternative approaches such as full restoration from backup media. This type of resynchronization is also known as restoring the snapshot from the copy or replica.