HP EVA Cluster Extension Software Administrator Guide (5697-2445, July 2013)

1 HP EVA Cluster Extension features
HP EVA Cluster Extension offers protection against application downtime due to a fault, failure, or
site disaster by extending a local cluster between data centers over metropolitan distance. HP EVA
Cluster Extension reinstates critical applications at a remote site within minutes of an adverse event,
integrating your open-system clustering software and HP EVA Continuous Access to automate
failover and failback between sites. This dual integration enables the cluster software to verify the
status of the storage and the server cluster. The cluster software can then make correct failover and
failback decisions, thus minimizing downtime and accelerating recovery.
Integration into cluster software
HP EVA Cluster Extension Software provides tight integration with the cluster software and is
managed as a resource of the clustered application service (like a disk or IP address).
HP EVA Cluster Extension integrates with Microsoft Failover Cluster (MSCS).
For supported cluster software versions, see the HP SPOCK website: http://www.hp.com/storage/
spock.
Graphical user interface
HP EVA Cluster Extension can be configured using the Failover Cluster Manager GUI. EVA Cluster
Extension offers full integration into the GUI so that you can easily set and change resource values.
CLI for easy integration
HP EVA Cluster Extension provides a CLI to enable disaster tolerant environments if no cluster
software is available for your operating system or if you want to integrate HP EVA Continuous
Access with your choice of cluster software.
This feature is useful if you use custom software to migrate application services from one system
to another or if you want HP EVA Cluster Extension to check the DR group member states to ensure
that you can automatically start your application service on the local storage system.
For detailed information, see CLI commands and utilities (page 67).
Disaster tolerance through geographical dispersion
Using two or more storage systems, HP EVA Continuous Access copies data to a remote data
center. Cluster solutions using HP EVA Continuous Access disk mirroring are called metropolitan
clusters or geographically dispersed clusters. In this arrangement, a server is a member of the same
cluster dispersed over two or more sites. In such clusters the server is relieved from writing any I/O
request to the disk more than one time because the storage system controls the replication process
(see Figure 1 (page 7)).
6 HP EVA Cluster Extension features