Appendix A Advanced Copy Function; Overview Of Advanced Copy Function; What Is Advanced Copy Function - Fujitsu ETERNUS DX60 Operation Manual

Appendix A
This appendix explains the Advanced Copy function of ETERNUS Disk storage system.
See
Refer to "Command References" in the
the commands used in Express.
A.1

Overview of Advanced Copy Function

A.1.1

What Is Advanced Copy Function?

Advanced Copy functions allow ETERNUS Disk storage system to carry out high-speed copying operations itself, with no need to draw
on server CPU resources. With Advanced Copy functions, at any point in time a business data volume can be copied to a separate copy
volume, quickly and within ETERNUS Disk storage system. Once the copy is complete, the copy volume can be separated from the
business volume ensuring no further updates to the business volume are applied to the copy volume. This allows the copy volume
data to be backed up to a tape device, as a point in time copy of the business data, while normal operations continue.
Advanced Copy Methods
Two types of Advanced Copy methods are supported:
One snapshot copy method (SnapOPC+) and three clone copy methods (EC, OPC and QuickOPC).
Of these types Express supports only the snapshot copy method.
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Snapshot creates a virtual point in time image of the original data.
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Clone make a full (physical) copy of the original data.
SnapOPC+
A function that creates a copy of the data prior to it being updated (Copy-on-Write).
As requires less copy volume capacity compared with clone, SnapOPC+ is ideal for copy operations for systems with relatively few
updates such as file servers.
EC (Equivalent Copy)
A function that maintains a synchronized copy of a business data volume on a copy volume (Mirroring method).
The business volume and copy volume are synchronized but can be separated at any required time (mirror suspend). The copy
volume can then be backed up to a tape device while business operations continue on the business volume.
Suspend/Resume functions can be used to re-establish the mirror by copying only updated data since the mirror was suspended.
OPC (One Point Copy)
A function that creates a copy of the business data volume at any point in time (Background Copy).
Data on the business volume is copied logically to a copy volume, quickly, as and when required.
The copy volume can be used for backup operation, to a tape device, without waiting for physical copy completion, while business
operations can continue on the business volume.
QuickOPC
A function that creates a copy of all the business data volume and subsequently only copies updated data (Background Copy).
This suits large database operation where backup times must be reduced.
Advanced Copy Function
ETERNUS SF AdvancedCopy Manager Operation Guide for Copy Control Module for details on
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