Hitachi F1500, Руководство по оборудованию

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Mode Category Description Default MCU/RCU
delay to the RI/O occurs constantly on this path due
to path failure or link delay, host MIH or time-out
may occur due to response time accumulation for
each RI/O retried within 5 seconds.
10. Even though the mode is set to ON, if Mainframe host
MIH time or Open host time-out time is set to 10
seconds or less, host MIH or time-out may occur due
to a path failure between controllers.
11. Operation commands are not available for quickly
switching to an alternate path.
12. The mode works for the pair on which an initial pair
creation or Resync operation is executed.
13. Micro-program downgrade to an unsupported version
cannot be executed unless all the TC Sync for z/OS or
TC Sync pairs are suspended or deleted.
14. For GAD pairs, the mode is effective if the firmware is
in a version that supports GAD.
15. For GAD pairs, the mode is effective if the microcode
is in a version that supports GAD.
16. The mode does not support paths between DKCs
using iSCSI. When iSCSI is used for paths between
DKCs, the time to switch to an alternate path cannot
be reduced. For this, if a failure occurs on a path
between DKCs in an environment where host time-
out time is short, a time-out may occur on the host
side. A time-out may also occur on the host side
when a failure occurs on an iSCSI path between
DKCs if DKC paths of Fibre and iSCSI coexist in an
environment where host time-out time is short so
that the configuration where DKC paths of Fibre and
iSCSI coexist is not supported too.
787 Compatible
FlashCopy(R) V2 This mode enables the batch prefetch copy.
Mode 787 = ON:
The batch prefetch copy is executed for an FCv2 pair and a
Preserve Mirror pair
Mode 787 = OFF (default):
The batch prefetch copy is not executed.
Notes:
1. When the mode is set to ON, the performance
characteristic regarding sequential I/Os to the
FCv2target VOL changes.
2. The mode is applied only when SOM 577 is set to OFF
3. The mode is applied if response performance for a
host I/O issued to the FCv2 target VOL is prioritized
OFF
803 Dynamic
Provisioning,
Data Retention
Utility
While a HDP pool VOL is blocked, if a read or write I/O is
issued to the blocked pool VOL, this mode can enable the
Protect attribute of DRU for the target DP-VOL.
Mode 803 = ON:
While a HDP pool VOL is blocked, if a read or write I/O is
issued to the blocked pool VOL, the DRU attribute is set to
Protect.
OFF
160 System option modes
Hitachi Virtual Storage Platform G1000, G1500, and Virtual Storage Platform F1500 Hardware Guide