Business continuance volume

In disk arrays, a business continuance volume (BCV) is EMC Corporation's term for an independently addressable copy of a data volume, that uses advanced mirroring technique for business continuity purposes.

Use
BCVs can be detached from the active data storage at a point in time and mounted on non-critical servers to facilitate offline backup or parallel computing. Once offline processes are completed, these BCVs can be either:


 * discarded
 * used as a source to recover the production data
 * re-attached (re-synchronized) to the production data again

Types
There are two types of BCVs:


 * A clone BCV is a traditional method, and uses one-to-one separate physical storage (splitable disk mirror)
 * least impact on production performance
 * high cost of the additional storage
 * persistent usage


 * A snapshot BCV, that uses copy on write algorithm on the production volume
 * uses only a small additional storage, that only holds the changes made to the production volume
 * lower cost of the additional storage
 * reads and writes impact performance of production storage
 * once snapshot storage fills up, the snapshot becomes invalid and unusable
 * short-term usage