2 overview of xp continuous access operations, Components – HP StorageWorks XP Remote Web Console Software User Manual
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2 Overview of XP Continuous Access operations
XP Continuous Access provides a storage-based hardware solution for disaster recovery, which
enables fast and accurate system recovery. After XP Continuous Access operations are established,
duplicate copies of data are automatically maintained for backup and disaster recovery purposes.
During normal XP Continuous Access 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. XP Continuous Access can also be used for data duplication and migration tasks.
XP Continuous Access 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 XP Continuous Access 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, XP Continuous Access Synchronous provides the highest
theoretical throughput.
XP Continuous Access Asynchronous represents a unique and outstanding disaster recovery solution
for large amounts of data spanning multiple volumes. The XP Continuous Access Asynchronous
group-based update sequence consistency solution enables fast and accurate database recovery
after a disaster, without time-consuming data recovery procedures. XP Continuous Access
Asynchronous (XP Continuous Access 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.
XP Continuous Access 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, XP Continuous Access Asynchronous provides the highest
possible theoretical throughput.
This overview of XP Continuous Access operations describes:
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“Remote copy operations” (page 12)
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“XP Continuous Access Asynchronous recordset operations” (page 17)
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“XP Continuous Access Asynchronous consistency group operations” (page 22)
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“XP Continuous Access volume pair status” (page 23)
Components
XP Continuous Access operations involve disk arrays at a primary and secondary (remote) site,
physical communications paths between these arrays, and XP Command View Advanced Edition
or XP Remote Web Console software. XP Continuous Access copies online data at the primary site
to volumes at the secondary site via dedicated Fibre Channel remote copy connections.
Host failover software is required for effective disaster recovery with XP Continuous Access.
shows XP Continuous Access components and the following functions:
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“Main and remote control units (MCUs and RCUs)” (page 8)
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“Volume pairs (P-VOLs and S-VOLs)” (page 9)
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Continuous Access XP Asynchronous consistency groups
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“Initiator ports and RCU target ports” (page 11)
Components
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