HP StorageWorks XP Remote Web Console Software - Manual (Page 11)

1 Overview of Copy Solutions
XRC for Mainframe
XRC for Mainframe is an asynchronous remote copy feature used for data backup in the event of a
disaster.
This product is used in mainframe systems and functionally compatible with Extended Remote Copy
(XRC). XRC for Mainframe is provided as a program product. It is compatible with System Data Mover
(SDM) in DFSMS (Data Facility Storage Management Subsystem), which is common to the XRC
environment. XRC for Mainframe operations are performed in the same manner as XRC operations,
by issuing XRC TSO commands from the host system to the storage system.
XRC for Mainframe temporarily stores the data written by the host at the primary site to the cache as
a sidefile. Upon request of the host at the secondary site, it asynchronously transfers the sidefile for
data backup to the secondary site.
Because XRC for Mainframe is an asynchronous remote copy feature, response time to the primary
site does not depend on the distance between the primary and secondary sites. You are able to use
the communication lines at the primary and secondary sites to have a long distance connection
between these sites. By using a common time stamp provided by the Sysplex timer, you are able to
guarantee that data is written at the secondary site in the same order as it is written at the primary
site.
In this software's operations, a group of logical volumes is processed as one session. The order of
writes at the secondary site is guaranteed in each session. You can register 4,096 sessions in one
disk subsystem, which enables you to have a large-scale remote copy system that involves multiple
hosts.
The program product must be installed in the disk subsystem at the primary site. For the installation
procedure, see the HP StorageWorks XP Remote Web Console user guide: HP XP12000 Disk Array,
HP XP10000 Disk Array, HP 200 Storage Virtualization System.
Other copy features
The storage system supports the following copy features that can be used in combination with the
software in mainframe systems.
Hitachi TrueCopy™ for z/OS
Hitachi TrueCopy™ for z/OS (TrueCopy z/OS) enables you to create copies of logical volumes in
two different subsystems at remote locations. You can manage data in mainframe systems by using
the Remote Control XP software or by using TSO and/or ICKDSF commands.
TrueCopy z/OS has synchronous and asynchronous copy modes. Synchronous mode can be used
for volume-based real-time data backup. Asynchronous mode enables you to back up data
asynchronously with the host write operation, so that the response time to the host will not be increased.
Synchronous mode can be used in conjunction with XRC for Mainframe to support disaster recovery
systems in three data center (3DC) configuration. See
Hitachi Extended Remote Copy for Mainframe user guide 11