Hitachi TrueCopy for IBM z/OS User and Reference Guide (T5211-96001, June 2007)

Overview of Hitachi for z/OS 1-5
Hitachi Universal Storage Platform V TrueCopy for IBM z/OS User’s Guide
Applications of TrueCopy Synchronous and TrueCopy
Asynchronous
TrueCopy provides a storage-based hardware solution for disaster recovery
which enables fast and accurate system recovery. Once TrueCopy operations
are established, duplicate copies of data are automatically maintained for
backup and disaster recovery purposes. During normal TrueCopy operations,
the primary volumes remain online to all hosts and continue to process both
read and write I/O operations. In the event of a disaster or system failure, the
secondary copy of data can be rapidly invoked to allow recovery with a very
high level of data integrity. TrueCopy can also be used for data duplication and
migration tasks.
TrueCopy Synchronous provides volume-based real-time data backup and is
ideal for high-priority data backup, duplication, and migration tasks. In the
event of a disaster or system failure at the primary site, the secondary
TrueCopy Synchronous data can be rapidly invoked to allow recovery at the
volume level with an extremely high level of data integrity.
TrueCopy Asynchronous represents a unique and outstanding disaster
recovery solution for large amounts of data which span multiple volumes. The
TrueCopy Asynchronous group-based update sequence consistency solution
enables fast and accurate database recovery, even after a “rolling” disaster,
without the need for time-consuming data recovery procedures. The TrueCopy
Asynchronous volume groups at the remote site can be recovered with full
update sequence consistency, but the updates will be behind the primary site
due to the asynchronous remote copy operations.
TrueCopy Asynchronous provides update sequence consistency for user-
defined groups of volumes (e.g., large databases) as well as protection for
write-dependent applications in the event of a disaster.