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Allowed
(-p al) [Linux only]
This parameter specifies the minimum permissive retry number of a SCSI command. The parameter is
available on disk devices, but ignored on tape devices.
Target Reset Mode
(-p tr) [RHEL5 only]
This parameter specifies whether the driver executes Target Reset command to the device or not.
The parameter is set to the optimum value for a general purpose, so usually this parameter does not need to
be changed.
LUN Reset Delay Timer
(-p lt) [Linux only]
This parameter specifies the time before processing the next SCSI command after a reset (LUN
Reset, etc.) command succeeded.
The parameter is set to the optimum value for a general purpose, so usually this parameter does
not need to be changed.
Scatter/Gather List
(-p sc) [Windows only]
This parameter specifies the number of memory lists per IO command, for all devices.
The parameter is set to the optimum value for a general purpose, so usually this parameter does not need to
be changed.
MSCS Mode
(-p ms) [Windows only]
If Microsoft Cluster Service (MSCS) on Windows Server 2003 is used, enable this parameter. If
JP1/HiCommand Dynamic Link Manager Software (HDLM) is insalled, or Windows Server 2008 is used, this
parameter is not necessary.
The parameter is set to the optimum value for a general purpose, so usually this parameter does not need to
be changed.
Queue Depth
(-p qd)
This parameter specifies maximum permissive I/O command number to queue per LU on the target device.
Since each target device have a maximum permissive I/O command number, so check the specification of
the target device.
(Example) If 17 LUs are used on a target device and the device have a port that can queue maximum 512
commands per second, and 4 systems are using the device. See the figure below.
The maximum number of the I/O available for queuing per LU is calculated with the following formula:
(Max. value of the I/O queuing number)÷(Number of LUs connected)
In this situation: 512 ÷ 17 = 30.11... Therefore, 30 or lower value should be set to this parameter.
System#0
System#1
Adapter#0
Fibre Channel Switch
Disk Device
LU0
LU1
LU2
LU3
LU4
System#0
System#2
Adapter#0
Adapter#0
Port#0
LU0
LU0
LU1
LU1
LU2
LU2
System#1
LU3
System#2
System#3
System#3
Adapter#0
LU0
LU1
LU2
LU3
LU4
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