Mode Category Description Default
MCU/R
CU
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.
c. The external volume is reserved by the host
5. As the VMA information is USP/NSC specific, this
mode does not need to be ON when the external
storage is other than USP/NSC.
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 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: 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 .
720 Universal
Volume
Manager
(Open)
Supports the Active Path Load Balancing (APLB) mode.
Mode 720 = ON: The alternate path of EVA (A/A) is used
in the APLB mode.
Mode 720 = OFF (default): The alternate path of EVA
(A/A) is used in the Single mode.
Note: Though online setting is available, the setting will
not be enabled until Check Paths is performed for the
mapped external device.
OFF .
721 Open 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 BED or DKU, are unavailable to
select.
Mode 721 = OFF (default): When a parity group is
uninstalled or installed, the operation is as before: the
OFF .
B-14
System option modes
Hitachi Unified Storage VM Block Module Hardware User Guide
To Next Page
Loading...
