Continuous Access Xp For The Xp12000/Xp10000; Overview Of Continuous Access Xp Operations - HP xp12000 User Manual

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Continuous Access XP for the XP12000/XP10000

HP StorageWorks Continuous Access XP creates and maintains duplicate copies of user data from a local
disk array on a remote disk array. These copies are useful for data duplication, backup, and disaster
recovery. Continuous Access XP has synchronous and asynchronous copy modes to accommodate a wide
variety of user requirements and data copy or movement scenarios. Continuous Access XP is used for open
systems data.
NOTE: This user guide applies only to Continuous Access XP Synchronous and Continuous Access XP
Asynchronous. It does not apply to Continuous Access XP Journal. For information about Continuous
Access XP Journal, see the HP StorageWorks Continuous Access XP Journal user guide.
If a system failure or disaster occurs at the primary (main) site, Continuous Access XP simplifies and
expedites disaster recovery procedures.
Continuous Access XP operations are nondisruptive and allow the primary (main) volume of each
Continuous Access XP volume pair to remain online to all hosts for read and write I/O operations. After
operations are established, Continuous Access XP operations continue unattended to provide continuous,
real-time data backup. Continuous Access XP operations can be performed across distances of up to 500
meters with a direct connection, 10 km (6.6 miles) using single-mode longwave optical fibre cables in a
switch configuration, 30 km (18.6 miles) using single-mode fiber with long-haul lasers in a switched
connection, and up to 100 km using DWDM in a switched configuration. Long-distance solutions are
provided, based on user requirements and workload characteristics, using approved channel extenders
and communication lines.
Continuous Access XP operations can be performed with Business Copy XP operations (see
Continuous Access XP
XP volumes. Continuous Access XP also supports LU Size Expansion (LUSE), Custom Volume Size (CVS),
and HP Cache LUN volumes. See
operations" on page 37 for more information.

Overview of Continuous Access XP operations

Continuous Access XP provides a storage-based hardware solution for disaster recovery, which enables
fast and accurate system recovery. After Continuous Access XP operations are established, duplicate
copies of data are automatically maintained for backup and disaster recovery purposes. During normal
Continuous Access XP operations, primary volumes remain online to all hosts and continue processing
read and write I/O operations. If a disaster or system failure occurs, the secondary copy of data can be
rapidly invoked to allow recovery with a very high level of data integrity. Continuous Access XP can also
be used for data duplication and migration tasks.
Continuous Access XP Synchronous provides volume-based real-time data replication and is ideal for
high-priority data backup, duplication, and migration tasks. If a disaster or system failure occurs at the
primary site, secondary Continuous Access XP Synchronous data can be rapidly invoked to allow recovery
at the volume level with an extremely high level of data integrity and currency. Up to a distance of
approximately 7-9 km, Continuous Access XP Synchronous provides the highest theoretical throughput.
Continuous Access XP Asynchronous represents a unique and outstanding disaster recovery solution for
large amounts of data spanning multiple volumes. The Continuous Access XP Asynchronous group-based
update sequence consistency solution enables fast and accurate database recovery after a disaster,
without time-consuming data recovery procedures. Continuous Access XP Asynchronous (Continuous
Access XP Async) volume groups at the remote site can be recovered with full update sequence
consistency, but data currency might be behind the primary site due to the asynchronous remote copy
operations.
Continuous Access XP Asynchronous provides update sequence consistency for user-defined groups of
volumes (such as large databases) and protection for write-dependent applications if a disaster occurs.
Beyond a distance of 7-9 km, Continuous Access XP Asynchronous provides the highest possible theoretical
throughput.
operations" on page 13) to provide multiple internal copies of Continuous Access
"Combining Continuous Access XP with other data management
Continuous Access XP user guide for the XP12000/XP10000
"Overview of
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