VVR enables you to create instant snapshots using the vxrvg snapshot command. This command takes snapshots of the data volumes in the RVG. However, the snapshot volumes are not part of the RVG. Each data volume in an RVG can have more than one snapshot volume. When creating full instant or space-optimized snapshots, the snapshot volumes do not need to be synchronized beforehand, therefore the snapshots are available instantly. The snapshot volumes are then synchronized later in the background.