NonStop S-Series Planning and Configuration Guide (G06.25+)

Glossary
HP NonStop S-Series Planning and Configuration Guide—523303-015
Glossary-59
local system
local system. (1) An on-site system or a system that is geographically near the user or
operator. (2) From the perspective of a particular SNETMON, the system or node on
which that SNETMON is running. (3) From the perspective of a system console
operator, the system to which the operator is logged on. Contrast with remote system
.
logical device name. The name assigned to an I/O process during its configuration. Other
processes use the logical device name when issuing Guardian procedure calls to the
I/O process.
logical device number (ldev). For a device or named process, the index into the
destination control table (DCT)
; or more precisely, into the named resource list (NRL).
Each device or named process in the system has an ldev.
logical disk volume. A hardware device or device pair that provides persistent, highly
accessible storage for data on a medium that is either magnetic or optical.
logical interface (LIF). A process that allows an application or another process to
communicate with data communications hardware.
logical memory unit (LMU). A group of four memory units. Memory on a processor and
memory board (PMB) is divided into two LMUs. One LMU contains memory units in
slots MS1 through MS4. The other LMU contains memory units in slots MS5 through
MS8. An LMU must have memory units installed either in all of its slots or in none of its
slots. See also memory unit
.
logical segment. A single data area consisting of one or more consecutive 128-kilobyte
unitary segments that is dynamically allocated by a process. The two types of logical
segments are selectable segments and flat segments. See also selectable segment
and flat segment
.
logic board (LB). (1) See cluster switch logic board. (2) A printed wiring assembly (PWA)
on which computer circuits (chips and wiring) are mounted. One type of logic board is a
processor and memory board (PMB). Another type is a multifunction I/O board
(MFIOB).
logical network partitioning. An HP NonStop™ TCP/IPv6 feature that allows you to divide
the system into separately addressed IP subnetworks whereby applications have
access only to a defined set of network interfaces (IP addresses).
logical unit number (LUN). The logical unit in the Enterprise Storage System (ESS) that
maps the LDEV onto a port
. Specification of the port and LUN specifies an LDEV.
login. The activity by which a user establishes a locally authenticated identity on a server.
Each login has one login name.
login name. A user name associated with a session.