Availability Guide for Application Design

Glossary
Availability Guide for Application Design—525637-004
Glossary-11
HP NonStop operating system
HP NonStop operating system. The operating system for NonStop systems, which
consists of the core and system services. The operating system does not include an
application program interface.
HP Object Monitoring Facility (OMF). An HP product that enables operators to supervise
objects such as processors, disks, files, and processes within the HP environment.
IDS. See intelligent device support (IDS).
I’m alive message. A special message sent between processors in a system to inform
recipient processors that the sending processor is running. Absence of this message
indicates a failed processor and enables other processors to start takeover.
immediate persistence. A process that is immediately restarted if it stops. These
processes are typically under the control of a monitor process. The monitor receives
notice from the operating system of the failure of a process it is responsible for and
restarts it.
information event. An event that is neither critical nor requires action, such as an event
that reports a change in the status of a process or device. Each subsystem determines
which events are information events by including a unique EMS token in the EMS
message. See also Event Management Service (EMS), critical event, and action event.
initialized persistence. A process that runs with a backup which takes over if the primary
process stops. The backup process is preinitialized by a single checkpoint operation
that occurs when the primary process finishes its initialization phase.
input/output process (IOP). A running program (part of the operating system) that
manages the I/O functions for one or more I/O controllers of the same type. A copy
runs in both the primary and the backup processors. The disk process (DP2) is one
type of I/O process.
Inspect. The HP debugging tool that can be used interactively to examine and modify the
execution of Guardian processes and COBOL requester programs.
inspection. A formal process involving a team of peer reviewers who, after reading all
related documentation, meet to visually test a document or piece of code against a
checklist of potential errors.
instrumentation. Program logic that provides information about the status of an object to
enable management of the object.
intelligent device. A device such as an automated teller machine, a point-of-sale device, or
a communications line, or a process such as a Guardian process that can
communicate with the Pathway environment through the intelligent device support
(IDS) facility, the Remote Server Call/MP (RSC/MP) product, or the Pathsend
procedure calls.