NonStop NS-Series Servers Site Preparation (H06.03+)

Glossary
HP Integrity NonStop NS-Series Site Preparation Guide—527836-005
Glossary-6
local area network (LAN)
local area network (LAN). A network that is located in a small geographical area and
whose communications technology provides a high-bandwidth, low-cost medium to
which low-cost nodes can be connected. One or more LANs can be connected to the
system such that the LAN users can access the system as if their workstations were
connected directly to it. Contrast with wide area network (WAN).
logical synchronization unit (LSU). The combination of the LSU logic board and the LSU
optics adapter. An LSU serves one logical processor.
LSU. See logical synchronization unit (LSU).
LSU enclosure. An enclosure that contains one to eight LSUs, a chassis, and AC power
distribution.
main service entrance. The enclosure containing connection panels and switchgear,
located at the point where the utility power lines enter the building.
maintenance switch. The Ethernet switch that links the maintenance entities in various
modular components to the HP NonStop Open System Management (OSM) Interface.
modular system. A complete server system in which processors, storage, input/output
components, and interconnect components are separate, self-contained, replaceable
modules. A modular system occupies one or more racks and allows independent
evolution and optimization of each kind of module.
modular cabinet. A cabinet with an integrated 19-inch rack equipped with a power
distribution unit (PDU), doors, slides, brackets, castors, leveling pads, and optional
side panels. See also cabinet.
module. (1) Part of the group, module, slot naming convention for uniquely identifying the
logical location of a component within a system. A module is a subset of a group, and it
is usually contained in an enclosure. A module contains one or more slots. A module
can consist of components sharing common interconnect, such as a backplane, or it
can be a logical grouping of components performing a particular function. See also
harmonic. (2) A set of I/O devices or services that share a common protocol and can
be controlled by a single module driver in the extensible I/O (XIO) subsystem.
MSIO. Modular storage I/O.
neutral. (1) The conductor used as the primary return for current during normal operation of
electrical equipment. (2) The junction of the legs in a wye circuit. See also wye.
(3) Generally at ground potential.
NonStop Technical Library. See HP NonStop™ Technical Library (NTL).
normal mode. Electromagnetic interference that occurs between current-carrying
conductors (for example, line to neutral).
NSAA. HP NonStop™ advanced architecture.