Glossary
A |
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application restart | Starting an application, usually on another node, after a failure. Application can be restarted |
| manually, which may be necessary if data must be restarted before the application can run |
| (example: Business Recovery Services work like this.) Applications can by restarted by an operator |
| using a script, which can reduce human error. Or applications can be started on the local or |
| remote site automatically after detecting the failure of the primary site. |
arbitrator | Nodes in a disaster tolerant architecture that act as |
| 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 |
| |
asymmetrical | A cluster that has more nodes at one site than at another. For example, an asymmetrical |
cluster | metropolitan cluster may have two nodes in one building, and three nodes in another building. |
| Asymmetrical clusters are not supported in all disaster tolerant architectures. |
asynchronous data | Local I/O will complete without waiting for the replicated I/O to complete; however, it is expected |
replication | that asynchronous data replication will process the I/Os in the original order. |
automatic failover | Failover directed by automation scripts or software (such as Serviceguard) and requiring no |
| human intervention. In a Continentalclusters environment, the |
| on the Recovery Cluster without intervention. See also application restart. |
B |
|
BC | (Business Copy) A PVOL or SVOL in an HP StorageWorks XP series disk array that can be split |
| from or merged into a normal PVOL or SVOL. It is often used to create a snapshot of the data |
| taken at a known point in time. Although this copy, when split, is often consistent, it is not usually |
| current. |
BCV | (Business Continuity Volume) An EMC Symmetrix term that refers to a logical device on the EMC |
| Symmetrix that may be merged into or split from a regular R1 or R2 logical device. It is often |
| used to create a snapshot of the data taken at a known point in time. Although this copy, when |
| split, is often consistent, it is not usually current. |
Continentalclusters configuration in which each cluster serves the roles of primary and recovery | |
configuration | cluster for different recovery groups. Also known as a mutual recovery configuration. |
Business Recovery | Service provided by a vendor to host the backup systems needed to run mission critical applications |
Service | following a disaster. |
C |
|
campus cluster | A single cluster that is geographically dispersed within the confines of an area owned or leased |
| by the organization such that it has the right to run cables above or below ground between |
| buildings in the campus. Campus clusters are usually spread out in different rooms in a single |
| building, or in different adjacent or nearby buildings. See also extended distance cluster. |
cascading failover | Cascading failover is the ability of an application to fail from a primary to a secondary location, |
| and then to fail to a recovery location on a different site. The primary location contains a |
| metropolitan cluster built with Metrocluster EMC SRDF, and the recovery location has a standard |
| Serviceguard cluster. |
client reconnect | Users access to the backup site after failover. Client reconnect can be transparent, where the |
| user is automatically connected to the application running on the remote site, or manual, where |
| the user selects a site to connect to. |
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 |
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