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

Glossary
HP NonStop S-Series Planning and Configuration Guide—523303-015
Glossary-24
directory tree
directory tree. A hierarchy of directories. In the Open System Services (OSS) environment,
directories are connected to each other in a branching hierarchical fashion such that
only one path exists between any two directories (if no backtracking occurs).
disconnecting means. A device, group of devices, or other means by which the conductors
of a circuit can be disconnected from their source of supply.
discovery. For the OSM and TSM client software, the process of identifying the resources
that exist on an HP NonStop™ S-series server. See also incremental discovery
and
initial discovery
.
disk bootstrap. A software entity residing on disk that is used to load the HP NonStop™
Kernel operating system image (OSIMAGE) into memory during a system load. A disk
that contains the disk bootstrap is referred to as a bootable disk. The disk bootstrap is
placed on the disk either as part of a tape load or as a result of the SCF CONTROL
DISK, REPLACEBOOT command.
disk cache. A temporary storage buffer into which data is read, retained, and perhaps
updated before being written to disk, for more efficient processing.
disk drive. A device that stores and accesses data on a magnetic disk. Random access to
addressable locations on a magnetic disk is provided by magnetic read/write heads.
See also volume
.
DISKGEN. A system generation option that invokes the DISKGEN program to copy directly
to disk the files necessary to generate an HP NonStop™ Kernel operating system.
DISKGEN can be used instead of a system image tape (SIT).
DISK object type. The Subsystem Control Facility (SCF) object type for all disk devices
attached to your system.
disk volume. See volume.
distributed system. A system that consists of a group of connected, cooperating
computers.
Distributed Systems Management (DSM). A set of tools used to manage HP NonStop™
S-series systems and Expand networks.
Distributed Systems Management/Software Configuration Manager (DSM/SCM). A
graphical user interface (GUI)-based program that installs new software and creates a
new HP NonStop™ Kernel operating system. DSM/SCM creates a new software
revision and activates the new software on the target system.
distribution subvolume (DSV). A subvolume containing program files for a particular
software product along with the release version update (RVU) document (softdoc) file
for that product. The format for a DSV name is Y
nnnnrrr or Rnnnnrrr, where nnnn
is the software product number and
rrr is the base version identifier (such as D20) or
software product revision (SPR) identifier (such as AAB).