Availability Guide for Problem Management

Glossary
Availability Guide for Problem Management–125509
Glossary-6
operations outage class
operations outage class. An outage class that includes errors caused by operations personnel
caused by accidents, inexperience, or malice.
operator message. The text displayed for a system operator that describes an event.
outage. Time during which the NonStop system is not capable of doing useful work because
of a planned or unplanned outage. From the end user’s perspective, an outage is any
time the application is not available.
outage class. A concept developed by Tandem to categorize the causes of outages. There are
five outage classes: physical, design, operations, environmental, and reconfiguration.
The first four categories describe unplanned outages. The reconfiguration outage class
includes all planned outages.
outage log. A record of system outages. An outage log can provide an accurate assessment
of availability. Tandem recommends that outages be measured in minutes rather than
percentages. See also outage minutes.
outage minutes. A metric recommended by Tandem for measuring outages that translates
percentages into minutes of down time per year.
PATHCOM. The command language interpreter used to communicate interactively with
PATHMON to configure and control Pathway.
PATHMON. The central control process for Pathway. PATHMON controls all processes and
devices in the Pathway environment and provides the means to configure, manage,
monitor, and change the Pathway configuration.
Pathway. The Tandem device and transaction control system that supports complex
applications in a network environment.
Pathway objects. Entities that are subject to independent reference or control. The Pathway
objects are PATHMON, PATHWAY, TCP, SERVER, PROGRAM, and TERM.
Pathway programmatic interface. A set of programmatic commands that allow you to write
management application programs that communicate directly with the Pathway central
control process (PATHMON) for configuration and control operations. The Pathway
programmatic interface is based on the Subsystem Programmatic Interface (SPI) portion
of Distributed Systems Management (DSM).
performance management. Activities that manage the performance of the production system
and network environment to ensure that the systems meet the business needs defined by
operations service-level agreements. One of the operations disciplines in the operations-
management model.
phantom device. A device that is configured but that is not physically present. You can make
a phantom device operational without having to bring your NonStop system down.
Configuring phantom devices is one way you can plan for future growth. Disk drives
are commonly configured as phantom devices.