HP StorageWorks Business Copy EVA V3.x Administrator Guide (T3680-96001, April 2005)

HP StorageWorks Business Copy EVA Administrator Guide 7
1 About HP StorageWorks Business Copy EVA
HP StorageWorks Business Copy EVA (hereafter referred to as local replication) is the HP product name for
licensed local replication features on HP StorageWorks Enterprise Virtual Arrays. This chapter describes
basic aspects of the product.
Local replication
Local replication allows you to quickly create local, point-in-time copies known as snapclones and
snapshots.
Snapclones
A snapclone is an independent, point-in-time copy (replica) of a virtual disk. The replica is created as a
fully allocated snapshot and, over time, becomes an independent virtual disk.
Snapshots
A snapshot is a virtual point-in-time copy (replica) of a virtual disk. Snapshots save space by copying
point-in-time data only when it changes on the source. A snapshot always depends on the source virtual
disk.
Snapshots can be demand allocated or fully allocated. A demand-allocated snapshot is a point-in-time
copy in which the allocated disk space can change on demand from an initial minimum up to the capacity
of the source at the moment of replication. A fully allocated snapshot is a virtual copy in which the
allocated disk space is fixed at the capacity of the source at the moment of replication.
Features and firmware versions
Local replication features vary with the firmware version. Thus, to administer local replication in a SAN,
you must know the firmware version on each array. Local replication is automatically installed with the
array firmware.
Licensing requirement
To enable local replication features on a given array, you must purchase an HP StorageWorks Business
Copy EVA license-to-use (LTU) for that array. When you purchase a local replication LTU, HP provides an
electronic license key, which you install using HP StorageWorks Command View EVA.
For more information, see Managing local replication licenses, page 13.
If you do not need local replication on a given array, you do not need a local replication license for the
array.
Storage management software requirement
To use local replication in a SAN, at least one installation of HP Command View EVA is required. A single
installation can manage all EVA arrays in a SAN.