IBM Advanced SerialRAID Adapters SA33-3285-02, User Manual

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Attributes Common to SSA Logical and SSA Physical Disks
adapter_a
Specifies either the name of one adapter that is connected to the device, or
none if no adapter is connected as adapter_a now.
adapter_b
Specifies either the name of one adapter that is connected to the device, or
none if no adapter is connected as adapter_b now.
primary_adapter
Specifies whether adapter_a or adapter_b is to be the primary adapter for this
device.
You can use the chdev command to modify this attribute to one of the values:
adapter_a, adapter_b or assign. If you set the value to assign, static load
balancing is performed when this device is made available, and the system
sets the value to either adapter_a, or adapter_b.
connwhere_shad
Holds a copy of the value of the connwhere parameter for this disk drive. SSA
disks drives cannot be identified by the location field that the lsdev command
gives, because they are connected in a loop, and do not have the
hardware-selectable addresses of SCSI devices. The serial numbers of the
disk drives are the only method of identification. The serial number of a
particular disk drive is written in the connwhere field of the CuDv entry for that
disk drive. This connwhere_shad attribute, which shadows the connwhere
value, allows you to display the connwhere value for an SSA device for a pdisk
or hdisk.
location
Describes, in text, the descriptions of the disk drives and their locations (for
example, drawer number 1, slot number 1). The user enters the information
for this attribute.
Attributes for SSA Logical Disks Only
pvid Holds the ODM copy of the PVID for this disk drive for an hdisk.
queue_depth
Specifies the maximum number of commands that the SSA disk device driver
dispatches to a logical disk. The default value is correct for normal operating
conditions. You can use the chdev command to modify this attribute. Valid
entry values are 0 through 200. A value of 0 resets the queue_depth to its
default value.
reserve_lock
Specifies whether the SSA disk device driver locks the device with a
reservation when it is opened for an hdisk.
size_in_mb
Specifies the size of the logical disk in megabytes.
Chapter 13. Using the Programming Interface
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