Overview Of Copy Services; Flashcopy - IBM TotalStorage DS6000 Attachment Manual

RAID-10 offers faster data reads and writes than RAID 5 because it does not need
to manage parity. However, with half of the DDMs in the group used for data and
the other half to mirror that data, RAID 10 disk groups have less capacity than
RAID 5 disk groups.

Overview of Copy Services

Copy Services is a collection of functions that provide disaster recovery, data
migration, and data duplication functions. Copy Services runs on the DS6000 series
and supports open systems and zSeries environments.
Many design characteristics of the DS6000 series and data copying and mirroring
capabilities of Copy Services features contribute to the protection of your data, 24
hours a day and seven days a week. A brief description of each of these licensed
features is provided below.
You can manage Copy Services functions through a command-line interface called
IBM TotalStorage DS CLI and a Web-based interface called IBM TotalStorage DS
Storage Manager. The DS Storage Manager allows you to set up and manage the
following types of data-copy features from any point from which network access is
available:
Point-in-time copy
Remote Mirror and Copy
Consider the following Copy Services information:
v The feature activation codes for Copy Services features (remote mirror and copy

FlashCopy

The IBM TotalStorage FlashCopy feature provides a point-in-time copy capability for
logical volumes. FlashCopy creates a physical point-in-time copy of the data, with
minimal interruption to applications, and makes it possible to access immediately
both the source and target copies.
The primary objective of FlashCopy is to create a copy of a source volume on the
target volume. This copy is called a point-in-time copy. When you initiate a
FlashCopy operation, a FlashCopy relationship is created between the source
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DS6000 Host Systems Attachment Guide
The point-in-time copy feature, which includes FlashCopy, enables you to
create full volume copies of data using source and target volumes that span
logical subsystems within a single storage unit. After the FlashCopy function
completes, you can immediately access both the source and target copies.
The remote mirror and copy feature copies data between volumes on two
or more storage units. When your host system performs I/O operations, the
source volume is copied or mirrored to the target volume automatically.
After you create a remote mirror and copy relationship between a source
volume and a target volume, the target volume continues to be updated
with changes from the source volume until you remove the relationship
between the volumes.
The following functions of remote mirror and copy are available:
v Metro Mirror
v Global Copy
v Global Mirror
and point-in-time copy) must be obtained and enabled on the DS Storage
Manager before you can begin using the features.