This document discusses layered volumes in VxVM. Layered volumes tolerate failure better and have greater redundancy than standard volumes. For example, a mirrored-striped layered volume has quicker recovery than a standard mirrored volume since each mirror covers less storage space. The document also discusses different types of layered volumes like mirror-striped and stripe-mirrored, how they provide redundancy and performance advantages over standard volumes, and some of their limitations.