Using High Availability Monitors (June 2007)

Glossary 97
Glossary
A-H
alert An event. A message sent to warn a
user or application when certain conditions
are met.
client The application that creates or
cancels requests to monitor particular
resources. The consumer of a resource status
message. A user of the Resource Monitor
framework. This user may browse resources,
request status, and make requests to have
resources monitored. Examples are
MC/ServiceGuard as it starts a package or
the HP SMH interface to EMS.
asynchronous monitor A monitor that
monitors resource instances (or resource
class) asynchronously. It is event driven and
send notifications when events occur. It does
not keep track of the current state or value of
each resource it monitors.
EMS (Event Monitoring Service) The
interface between resource monitors, the
client and target applications.
emscli A command line utility that is used
to configure and manage persistent
monitoring requests for Event Monitoring
Service (EMS) monitors, such as, HA
Monitors, Hardware Monitors and Kernel
Monitors.
EMS Framework A set of APIs together
with the Registrar process and the resource
dictionary, which allow client applications to
request that resources be monitored and a
target application be notified.
event An alert.
HA High Availability.
I-K
ITO HP OpenView IT/Operations, formerly
known as Operations Center. It is a software
application that provides central operations
and problem management for a multi-vendor
distributed system.
L
logical extent The basic allocation unit for
a logical volume is called a logical extent. For
mirrored logical volumes, either two or three
physical extents are mapped for each logical
extent, depending on whether you are using
2-way or 3-way mirroring.
logical volume A collection of disk space
from one or more disks. Each collection
appears to the operating system as a single
disk. Like disks, logical volumes can be used
to hold file systems, raw data areas, dump
areas, or swap areas. Unlike disks, logical
volumes can be given a size when they are
created, and a logical volume can later be
expanded or reduced. Also, logical volumes
can be spread over multiple disks.
LUN (Logical Unit Numbers) A logical disk
device composed of one or more physical disk
mechanisms, typically configured into a
RAID level.
LVM (Logical Volume Manager) Manages
disks in volume groups, and allows you to
create logical and physical volume
groupings.
M
MIB (Management Information Base). A
document that describes objects to be
managed. A MIB is created using a grammar
defined in “Structure of Management