Hitachi Virtual Storage Platform F400, System Administrator Manual, Page: 340 / 368

Mode Category Description Default MCU/RCU
1080 Global-active
device
Universal
Volume
Manager
This SOM is intended for a case that multiple
external connection paths are connected to a Target
port on an external system with a quorum disk and
there is a path whose performance degrades. For
such a case, this SOM can eliminate impacts on
commands run for other external devices that share
the Target port with the quorum disk on the external
system by setting the time to run a reset command
for the Target port to be the same (15 seconds) as
that to run other commands for the other external
devices.
Mode 1080 = ON: The time to run the reset
command for the quorum disk on the external
system is 15 seconds to eliminate the impacts on
commands run for the other external devices that
share the Target port with the quorum disk on the
external system.
If a response to ABTS is delayed for 12 seconds or
longer, the quorum disk may be blocked.
Mode 1080 = OFF (default): The time to run a reset
command for the quorum disk when performance of
a path degrades is 3 seconds so that a retry is
performed by an alternate path to avoid quorum
disk blockage.
Notes:
1. This SOM is applied if avoiding impacts on
commands for other external devices sharing a
Target port on an external system side with a
quorum disk is prioritized over preventing
quorum disk blockage when a response to ABTS
is delayed.
The delay is caused due to path performance
degradation in a configuration where the Target
port is shared between external devices and the
quorum disk.
2. When connection performance degradation
occurs, the quorum disk blockage is more likely
to occur.
OFF -
System option modes
Appendix B: System option modes
System Administrator Guide for VSP Gx00 models and VSP Fx00 models 340