HP XP P9500 Storage - Manual (Page 7)

1 Business Copy Z overview
Business Copy Z (BC Z) uses local mirroring technology to create and maintain a full copy of any
volume in the storage system.
With BC Z software you can create one or more copies of a data volume within the same storage
system. You can use BC Z copies as backups, with secondary host applications, for data mining,
for testing, and other uses — while business operations continue without stopping host application
I/O to the production volume.
This guide provides instructions for planning, configuring, operating, maintaining, and
troubleshooting a BC Z system.
How Business Copy Z works
A pair is created when you:
•
Select a volume that you want to duplicate. This becomes the P-VOL volume (P-VOL).
•
Identify another volume to contain the copy. This becomes the secondary volume (S-VOL).
•
Associate the P-VOL and S-VOLs.
•
Perform the initial copy.
During the initial copy, the P-VOL remains available for read/write. After the copy is completed,
subsequent write operations to the P-VOL are regularly duplicated to the S-VOL.
The P-VOL and S-VOLs remain paired until they are split. The P-VOL for a split pair continues to be
updated but data in the S-VOL remains as it was at the time of the split. The S-VOL contains a
mirror image of the original volume at that point in time.
•
S-VOL data is consistent and usable. It is available for read/write access by secondary host
applications.
•
Changes to the P-VOL and S-VOLs are managed by differential bitmaps.
•
You can pair the volumes again by resynchronizing the update data from P-VOL-to-S-VOL, or
from S-VOL-to-P-VOL, as circumstance dictates.
NOTE: In Remote Web Console (RWC), the source volume is called P-VOL and the destination
volume is called S-VOL.
Hardware and software components
A typical configuration consists of a P9500 storage system, a host connected to the storage system,
BC Z software, a P-VOL, a S-VOL or volumes, and interface tools for operating BC Z.
Interface tools include the RWC graphical user interface (GUI) and Business Continuity Manager
(BCM), IBM PPRC host software functions, IBM DFSMSdss host software functions, and RAID
Manager .
The following shows a typical configuration.
How Business Copy Z works 7