HP XP P9500 Owner's Manual page 43

Table 1 1 System option modes (continued)
Mode Category
784 Continuous Access
Synchronous
2 of 2
Continuous Access
Synchronous for
Mainframe
787 Compatible
FlashCopy
803 Dynamic
Provisioning,
Data Retention
Utility
Description
4. To apply the mode to TC Sync for z/OS, MCU and RCU must
be RAID600 or RAID700 and micro-program must be the
support version on both sides.
5. If a failure occurs on the switched path between DKCs,
Mainframe host MIH or Open server time-out may occur.
(Continued below)
Notes: (continued)
6. If an MP to which the path between DKCs belongs is
overloaded, switching to an alternate path delays and host MIH
or time-out may occur.
7. If an RI/O retry occurs due to other factors than RI/O MIH (5
sec), such as a check condition report issued from RCU to MCU,
the RI/O retry is performed on the same path instead of an
alternate path. If a response 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.
8. 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 DKCs.
9. Operation commands are not available for promptly
switching to an alternate path.
10. The mode works for the pair for which initial pair creation
or Resync operation is executed.
1 1. 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.
12. See the appendix of the SOM for operational specifications
in each combination of MCU and RCU.
This mode enables the batch prefetch copy.
Mode 787 = ON:
The batch prefetch copy is executed for an FC Z 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
While a THP 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 THP 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.
Mode 803 = OFF (default):
While a THP pool VOL is blocked, if a read or write I/O is issued
to the blocked pool VOL, the DRU attribute is not set to Protect.
Notes:
System option modes, host modes, and host mode options
Default MCU/RCU
OFF MCU/RCU
OFF ..
OFF ..
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