IBM System Storage DCS3700 Installation, User's, And Maintenance Manual page 194

Microsoft Cluster Server (MSCS). MSCS, a feature of
Windows NT Server (Enterprise Edition), supports the
connection of two servers into a cluster for higher
availability and easier manageability. MSCS can
automatically detect and recover from server or
application failures. It can also be used to balance
server workload and provide for planned maintenance.
mini hub. An interface card or port device that
receives short-wave fiber channel GBICs or SFPs. These
devices enable redundant fibre channel connections
from the host computers, either directly or through a
fibre channel switch or managed hub, over optical fiber
cables to the DS4000 Storage Server controllers. Each
DS4000 controller is responsible for two mini hubs.
Each mini hub has two ports. Four host ports (two on
each controller) provide a cluster solution without use
of a switch. Two host-side mini hubs are shipped as
standard. See also host port, gigabit interface converter
(GBIC), small form-factor pluggable (SFP).
mirroring. A fault-tolerance technique in which
information on a hard disk is duplicated on additional
hard disks. See also remote mirroring.
model. The model identification that is assigned to a
device by its manufacturer.
MSCS. See Microsoft Cluster Server.
network management station (NMS). In the Simple
Network Management Protocol (SNMP), a station that
runs management application programs that monitor
and control network elements.
NMI. See non-maskable interrupt.
NMS. See network management station.
non-maskable interrupt (NMI). A hardware interrupt
that another service request cannot overrule (mask). An
NMI bypasses and takes priority over interrupt
requests generated by software, the keyboard, and
other such devices and is issued to the microprocessor
only in disastrous circumstances, such as severe
memory errors or impending power failures.
node. A physical device that allows for the
transmission of data within a network.
node port (N_port). A fibre-channel defined hardware
entity that performs data communications over the
fibre-channel link. It is identifiable by a unique
worldwide name. It can act as an originator or a
responder.
nonvolatile storage (NVS). A storage device whose
contents are not lost when power is cut off.
N_port. See node port.
NVS. See nonvolatile storage.
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IBM System Storage DCS3700: Installation, User, and Maintenance Guide
NVSRAM. Nonvolatile storage random access
memory. See nonvolatile storage.
Object Data Manager (ODM). An AIX proprietary
storage mechanism for ASCII stanza files that are
edited as part of configuring a drive into the kernel.
ODM. See Object Data Manager.
out-of-band. Transmission of management protocols
outside of the fibre-channel network, typically over
Ethernet.
partitioning. See storage partition.
parity check. (1) A test to determine whether the
number of ones (or zeros) in an array of binary digits is
odd or even. (2) A mathematical operation on the
numerical representation of the information
communicated between two pieces. For example, if
parity is odd, any character represented by an even
number has a bit added to it, making it odd, and an
information receiver checks that each unit of
information has an odd value.
PCI local bus. See peripheral component interconnect
local bus.
PDF. See portable document format.
performance events. Events related to thresholds set
on storage area network (SAN) performance.
peripheral component interconnect local bus (PCI
local bus). A local bus for PCs, from Intel, that
provides a high-speed data path between the CPU and
up to 10 peripherals (video, disk, network, and so on).
The PCI bus coexists in the PC with the Industry
Standard Architecture (ISA) or Extended Industry
Standard Architecture (EISA) bus. ISA and EISA boards
plug into an IA or EISA slot, while high-speed PCI
controllers plug into a PCI slot. See also Industry
Standard Architecture, Extended Industry Standard
Architecture.
polling delay. The time in seconds between successive
discovery processes during which discovery is inactive.
port. A part of the system unit or remote controller to
which cables for external devices (such as display
stations, terminals, printers, switches, or external
storage units) are attached. The port is an access point
for data entry or exit. A device can contain one or more
ports.
portable document format (PDF). A standard
specified by Adobe Systems, Incorporated, for the
electronic distribution of documents. PDF files are
compact; can be distributed globally by e-mail, the
Web, intranets, or CD-ROM; and can be viewed with
the Acrobat Reader, which is software from Adobe
Systems that can be downloaded at no cost from the
Adobe Systems home page.