IBM System storage DS6000 Series, Attachment Manual

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IBM TotalStorage Multipath Subsystem Device
Driver (SDD)
Software that is designed to support the
multipath configuration environments of
the DS6000. The SDD resides in a host
system with the native disk device driver.
IBM TotalStorage Resiliency Family
A set of hardware and software features
and products, as well as integrated
software and services that are available
on theIBM TotalStorage DS6000 and the
IBM TotalStorage Enterprise Storage
Server, Models 750 and 800.
IML See initial microcode load .
implicit allegiance
In Enterprise Systems Architecture/390, a
relationship that a control unit creates
between a device and a channel path
when the device accepts a read or write
operation. The control unit guarantees
access to the channel program over the
set of channel paths that it associates with
the allegiance.
initial microcode load (IML)
The action of loading microcode for a
computer into that computer’s storage.
initial program load (IPL)
The action of loading software into a
computer, typically an operating system
that controls the computer.
initiator
A SCSI device that communicates with
and controls one or more targets. Contrast
with target .
i-node The internal structure in an AIX operating
system that describes the individual files
in the operating system. It contains the
code, type, location, and owner of a file.
input/output (I/O)
Pertaining to (a) input, output, or both or
(b) a device, process, or channel involved
in data input, data output, or both.
input/output configuration data set
A configuration definition built by the I/O
configuration program (IOCP) and stored
on disk files associated with the processor
controller.
interleave
To automatically create two striped
partitions across the drives in a RAID-5
array, both of which use the
count-key-data (CKD) record format.
Internet Protocol (IP)
In the Internet suite of protocols, a
protocol without connections that routes
data through a network or interconnecting
networks and acts as an intermediary
between the higher protocol layers and
the physical network. The upper layer
supports one or more logical protocols (for
example, a SCSI-command protocol and a
zSeries command protocol). Refer to ANSI
X3.230-199 x . The IP acronym is the IP in
TCP/IP. See also Transmission Control
Protocol/Internet Protocol .
invalidate
To remove a logical data unit from cache
memory because it cannot support
continued access to the logical data unit
on the device. This removal might be the
result of a failure within the storage server
or a storage device that is associated with
the device.
I/O See input/output .
I/O adapter (IOA)
An input-output adapter on the PCI bus.
IOCDS
See input/output configuration data set .
IOCP See I/O Configuration Program .
I/O Configuration Program (IOCP)
A program that defines to a system all the
available I/O devices and channel paths.
I/O device
An addressable read and write unit, such
as a disk drive device, magnetic tape
device, or printer.
I/O interface
An interface that enables a host to
perform read and write operations with its
associated peripheral devices.
I/O Priority Queueing
A facility in the Workload Manager of
zSeries that enables the system
administrator to set priorities for queueing
I/Os from different system images. See
also multiple allegiance and parallel
access volume .
I/O processor (IOP)
Controls input-output adapters and other
devices.
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DS6000 Host Systems Attachment Guide