Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access EVA A.05.01

disaster recovery The process of restoring access to applications and data after a disaster. Disaster recovery can
be manual, meaning human intervention is required, or it can be automated, requiring little or
no human intervention.
disaster tolerant The characteristic of being able to recover quickly from a disaster. Components of disaster
tolerance include redundant hardware, data replication, geographic dispersion, partial or complete
recovery automation, and well-defined recovery procedures.
E, F
Environment File Metrocluster uses a configuration file that includes variables that define the environment for the
Metrocluster to operate in a Serviceguard cluster. This configuration file is referred to as the
Metrocluster environment file. This file needs to be available on all nodes in the cluster for
Metrocluster to function successfully.
failback Failing back from a backup node, which may or may not be remote, to the primary node that
the application normally runs on.
failover The transfer of control of an application or service from one node to another node after a failure.
Failover can be manual, requiring human intervention, or automated, requiring little or no human
intervention.
G, H, I, J, K, L
heartbeat network A network that provides reliable communication among nodes in a cluster, including the
transmission of heartbeat messages, signals from each functioning node, which are central to the
operation of the cluster, and which determine the health of the nodes in the cluster.
local failover Failover on the same node; this most often applied to hardware failover, for example local LAN
failover is switching to the secondary LAN card on the same node after the primary LAN card
has failed.
LUN (Logical Unit Number) A SCSI term that refers to a logical disk device composed of one or more
physical disk mechanisms, typically configured into a RAID level.
M, N
manual failover Failover requiring human intervention to start an application or service on another node.
Metrocluster A Hewlett-Packard product that allows a customer to configure an Serviceguard cluster as a
disaster tolerant metropolitan cluster.
Metrocluster
Environment File
Metrocluster uses a configuration file that includes variables that define the environment for the
Metrocluster to operate in a Serviceguard cluster. This configuration file is referred to as the
Metrocluster environment file. This file needs to be available on all nodes in the cluster for
Metrocluster to function successfully.
metropolitan
cluster
A cluster that is geographically dispersed within the confines of a metropolitan area requiring
right-of-way to lay cable for redundant network and data replication components.
mission critical
application
Hardware, software, processes and support services that must meet the uptime requirements of
an organization. Examples of mission critical application that must be able to survive regional
disasters include financial trading services, e-business operations, 911 phone service, and patient
record databases.
multiple points of
failure (MPOF)
More than one point of failure that can bring down an Serviceguard cluster.
notification A message that is sent following a cluster or package event.
O-P
PV links A method of LVM configuration that allows you to provide redundant disk interfaces and buses
to disk arrays, thereby protecting against single points of failure in disk cards and cables.
Q
quorum See See cluster quorum..
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