Building Disaster Recovery Serviceguard Solutions Using Metrocluster with 3PAR Remote Copy

Glossary
A — C
3PAR Remote Copy The 3PAR storage systems are configured for use in data replication from one 3PAR storage
system unit to another. This type of physical data replication is a part of the Metrocluster with
3PAR Remote Copy.
3PAR Remote Copy A facility provided by the Continuos Access software option available with the HP StorageWorks
P9000 Disk Array family, HP StorageWorks E Disk Array XP series. This facility enables physical
data replication between P9000 or XP series disk arrays.
arbitrator Nodes in a disaster tolerant architecture that act as tie-breakers in case all of the nodes in a data
center go down at the same time. These nodes are full members of the Serviceguard cluster and
must conform to the minimum requirements. The arbitrator must be located in a third data center
to ensure that the failure of an entire data center does not bring the entire cluster down. See also
quorum server.
automatic failover Failover directed by automation scripts or software (such as Serviceguard) and requiring no
human intervention. In a Continentalclusters environment, the start-up of package recovery groups
on the Recovery Cluster without intervention. See also.
cluster An Serviceguard cluster is a networked grouping of HP 9000 and/or HP Integrity Servers series
800 servers (host systems known as nodes) having sufficient redundancy of software and hardware
that a single failure will not significantly disrupt service. Serviceguard software monitors the health
of nodes, networks, application services, EMS resources, and makes failover decisions based on
where the application is able to run successfully.
Continentalclusters
A group of clusters that use routed networks and/or common carrier networks for data replication
and cluster communication to support package failover between separate clusters in different
data centers. Continentalclusters are often located in different cities or different countries and can
span 100s or 1000s of kilometers.
D
data center A physically proximate collection of nodes and disks, usually all in one room.
data currency Whether the data contain the most recent transactions, and/or whether the replica database has
all of the committed transactions that the primary database contains; speed of data replication
may cause the replica to lag behind the primary copy, and compromise data currency.
data replication The scheme by which data is copied from one site to another for disaster tolerance. Data replication
can be either physical (see physical data replication) or logical (see logical data replication). In
a Continentalclusters environment, the process by which data that is used by the cluster packages
is transferred to the Recovery Cluster and made available for use on the Recovery Cluster in the
event of a recovery.
disaster An event causing the failure of multiple components or entire data centers that render unavailable
all services at a single location; these include natural disasters such as earthquake, fire, or flood,
acts of terrorism or sabotage, large-scale power outages.
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 recovery
services
Services and products offered by companies that provide the hardware, software, processes,
and people necessary to recover from a disaster.
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.
disaster tolerant
architecture
A cluster architecture that protects against multiple points of failure or a single catastrophic failure
that affects many components by locating parts of the cluster at a remote site and by providing
data replication to the remote site. Other components of disaster tolerant architecture include
100 Glossary