Backup (Advanced Copy)

The Advanced Copy function (high-speed copying function) enables data backup (data replication) at any point without stopping business operations.

For an ETERNUS DX backup operation, data can be replicated without placing a load on the business server. Large amounts of data can be replicated by coordinating the timing of business access so data protection measures can be applied separately from those of operation processes.

An example of an Advanced Copy operation using ETERNUS SF AdvancedCopy Manager is shown below.

Figure: Example of Advanced Copy

There are two types of Advanced Copy: a local copy that is performed within a single ETERNUS DX and a remote copy that is performed between multiple ETERNUS DX storage systems.

Local copy functions include One Point Copy (OPC), QuickOPC, SnapOPC, SnapOPC+, and Equivalent Copy (EC), and remote copy functions include Remote Equivalent Copy (REC).

The following table shows ETERNUS related software for controlling the Advanced Copy function.

Table: Control Software (Advanced Copy)
Control software	Feature	Available copy methods
ETERNUS Web GUI / ETERNUS CLI	The copy functions can be used without optional software.	SnapOPC+
RESTful API	The copy functions can be used without optional software.	SnapOPC SnapOPC+ QuickOPC OPC REC
ETERNUS SF AdvancedCopy Manager	ETERNUS SF AdvancedCopy Manager supports various OSs and ISV applications, and enables the use of all the Advanced Copy functions. This software can also be used for backups that interoperate with Oracle, SQL Server, Exchange Server, or Symfoware Server without stopping operations.	SnapOPC SnapOPC+ QuickOPC OPC EC REC

A copy is executed for each LUN. With ETERNUS SF AdvancedCopy Manager, a copy can also be executed for each logical disk (which is called a partition or a volume depending on the OS). For details on copies that use RESTful API, refer to "RESTful API Reference".

A copy cannot be executed if another function is running in the storage system or the target volume. For details on the functions that can be executed simultaneously, refer to Combinations of Functions That Are Available for Simultaneous Executions.

Table: List of Advanced Copy Specifications
Specification	ETERNUS DX600 S6	ETERNUS DX900 S6 ETERNUS DX8900 S6
Maximum number of sessions (*1)	8,192	32,768
Maximum number of copy source and copy destination areas per volume (1) (2)	32
Maximum number of copy destinations per copy source area in a multi-copy (1) (3)	8
Maximum number of sessions for which the Concurrent Suspend function is set (*4)	8,192	16,384
Maximum number of sessions for which the concurrent OPC function is set (*4)	1,024

*1	:	The total maximum number of copy sessions for local copies and remote copies. Note the following items for SnapOPC+: For the maximum number of sessions, count one generation as one session. When handling this item as the "number of copy source and copy destination areas" for this item, count the copy source areas in the generation group as one. For the copy destination area, count one generation as one. When handling this item as the "number of multi-copy sessions", count the multi-copy sessions in the generation group as one. For REC, copy sessions that are in the Suspend state are counted as a running copy session. During multi-copy or Cascade Copy, each copy session is counted as a single session. All sessions are assumed to be running simultaneously.
*2	:	For local copies, this is the maximum number of areas that can be set as the copy source and copy destination. Note that if a multi-copy is being performed, the number of areas that can be set as the copy source and the copy destination decreases. Up to one copy destination area can be set in an SDV (SnapOPC/SnapOPC+ copy destination volume). Copy source areas cannot be set in an SDV (except for OPC Restoration). For remote copies, this is equivalent to the maximum number of sessions (number of session that include the number of copy sessions to be copy sources and copy destinations) per volume.
*3	:	A copy that is performed from the same copy source area to multiple copy destination areas is called a multi-copy. For details, refer to Multi-Copy in Available Advanced Copy Combinations. For remote copies, this is equivalent to the maximum number of sessions (number of session that include the number of copy sessions to be copy sources and copy destinations) per area.
*4	:	"Maximum number of sessions for which the Concurrent Suspend function is set" and "Maximum number of sessions for which the concurrent OPC function is set" are specifications of local copy.

Caution

The copy table size must be set in advance when Advanced Copy is used. For more details, refer to "Web GUI User's Guide".
A copy session cannot use an area that partially or fully overlaps the copy destination area of another copy session as a copy destination.
The response and batch processing times may be affected due to business operation of a copy source volume and copy destination volume while Advanced Copy is running.