Mode
Category
Description
Default
MCU/RCU
6.
Set the mode to OFF when the following conditions
are met.
a. RAID700 70-03-3x-00/00 or higher version is used
on the storage system
b. An external volume to which Nondisruptive
Migration (NDM) attribute is set exists.
704
Open and
Mainframe
To reduce the chance of MIH, this option can reduce the
priority of SI, VM, CoW Snapshot, Flash Copy or Resync
copy internal IO requests so that host IO has a higher
priority. This mode creates new work queues where these
jobs can be assigned with a lower priority.
Mode 704 = ON:
Copy processing requested is registered into a newly
created queue so that the processing is scheduled with
lower priority than host I/O.
Mode 704 = OFF: (Default)
Copy processing requested is not registered into a newly
created queue. Only the existing queue is used.
Note:
If the PDEV is highly loaded, the priority of Read/Write
processing made by SI, VM, Snapshot, Compatible
FlashCopy
®
V2 or Resync may become lower. As a
consequence the copy speed may be slower.
OFF
721
Open and
Mainframe
When a parity group is uninsulated or installed, the
following operation is performed according to the setting of
mode 721.
Mode 721 = ON:
When a parity group is uninstalled or installed, the LED of
the drive for uninstallation is not illuminated, and the
instruction message for removing the drive does not
appear. Also, the windows other than that of parity group,
such as DKA or DKU, are unavailable to select.
Mode 721 = OFF (default):
When a parity group is uninstalled or installed, the
operation is as before: the LED of the drive is illuminated,
and the drive must be unmounted and remounted.
Notes:
1.
When the RAID level or emulation type is changed for
the existing parity group, this option should be
applied only if the drive mounted position remains
the same at the time of the parity group
uninstallation or installation.
2.
After the operation using this option is completed,
the mode must be set back to OFF; otherwise, the
LED of the drive to be removed will not be
illuminated at subsequent parity group uninstalling
operations.
OFF
System option modes
151
Hitachi Virtual Storage Platform G1000, G1500, and Virtual Storage Platform F1500 Hardware Guide