is transferred to the Recovery Cluster and made available for use on the Recovery Cluster in the

 

event of a recovery.

database

A software-based logical data replication scheme that is offered by most database vendors.

replication

 

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 protection

(Don’t use this term?) Processes, tools, hardware, and software that provide protection in the

 

event of an extreme occurrence that causes application downtime such that the application can

 

be restarted at a different location within a fixed period of time.

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 and products offered by companies that provide the hardware, software, processes,

services

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

A cluster architecture that protects against multiple points of failure or a single catastrophic failure

architecture

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

 

redundant links, either for networking or data replication, that are installed along different routes,

 

and automation of most or all of the recovery process.

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.

ESCON

Enterprise Storage Connect. A type of fiber-optic channel used for inter-frame communication

 

between EMC Symmetrix frames using EMC SRDF or between HP StorageWorks E P9000 or XP

 

series disk array units using Continuous Access P9000 or XP.

event log

The default location (/var/opt/resmon/log/cc/eventlog) where events are logged on

 

the monitoring Continentalclusters system. All events are written to this log, as well as all

 

notifications that are sent elsewhere.

extended distance

A cluster with alternate nodes located in different data centers separated by some distance.

cluster

Formerly known as campus cluster.

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.

filesystem

The process of replicating filesystem changes from one node to another.

replication

 

G

 

gatekeeper

A small EMC Symmetrix device configured to function as a lock during certain state change

 

operations.

H, I

 

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.

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