Fujitsu ETERNUS DX S5 Series, Руководство по конструкции

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*2: When issuing a re-copy request for copy session 1 (a request to copy only the data that has been updated after all data is copied),
the modified data size should conform to the sizes shown in
Table 50 .
For example, when a QuickOPC session is created at a resolution of 2, the modified data size should be less than 2TB. The
"Resolution" for QuickOPC sessions can be checked on the [Advanced Copy (QuickOPC Sessions)] screen.
Table 50 Modified Data Size for Each QuickOPC Resolution
Resolution 1 2 4 8 16 32 64
Modified data size Less than 1TB Less than 2TB Less than 4TB Less than 8TB Less than 16TB Less than 32TB Less than 64TB
If a re-copy request is issued for a larger size, the command for the re-copy request may time out and fail. The current "Modified
Data Size" for copy session 1 can be checked on the [Advanced Copy (QuickOPC Sessions)] screen. If an error occurs for copy session
1, perform one of the following operations instead.
• When performing a continuous Cascade Copy of QuickOPC
After the phase for copy session 2 becomes "Tracking", delete copy session 1. After changing the copy resolution of the ETERNUS
DX, re-create copy session 1. For details on changing the resolution, refer to the "Modify Copy Table Size" section in "ETERNUS
Web GUI User's Guide".
•
When performing a temporary recovery
Use a Cascade Copy of QuickOPC (copy session 1) and OPC (copy session 2).
• When backing up two generations
Use a multi-copy that is configured with QuickOPC and QuickOPC.
*3: To suspend a Cascade Copy where session 2 is an EC or REC session, perform the Suspend command after the physical copy for copy
session 1 is complete.
*4: A Cascade Copy cannot be performed when a copy source and destination volume is in an older ETERNUS storage system model.
*5: When copy session 1 uses the REC Consistency mode, the data transmission sequence of copy session 1 is guaranteed, but the data
transmission sequence of copy session 2 is not guaranteed.
Table 51 shows the supported combinations when adding a copy session to a copy source volume where a
copy session has already been configured.
Table 51 Available Cascade Copy Combinations (When a Cascade Copy Performs Session 2 Followed by
Session 1)
Copy session
1
Copy session 2
OPC QuickOPC SnapOPC EC
REC
synchronous
transmissio
n
REC Stack
mode
REC
Consistency
mode
OPC
¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡
QuickOPC
¡ ¡
(*1)
¡ ¡ ¡ ¡ ¡ ¡
SnapOPC
´ ´ ´ ´ ´ ´ ´ ´
´ ´ ´ ´ ´ ´ ´ ´
EC ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡
REC
synchronous
transmission
¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡
REC Stack
mode ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡
REC
Consistency
mode ¡ ¡ ¡ ¡ ¡ ¡ (*2) ¡ ¡ (*2)
2. Basic Functions
Backup (Advanced Copy)
117 Design Guide