A global cluster links clusters at separate locations and enables wide-area failover and disaster recovery.
Local clustering provides local failover for each site or building. Campus and replicated cluster configurations offer protection against disasters that affect limited geographic regions. Large scale disasters such as major floods, hurricanes, and earthquakes can cause outages for an entire city or region. In such situations, you can ensure data availability by migrating applications to sites located considerable distances apart.
Figure: Global cluster shows a global cluster configuration.
In a global cluster, if an application or a system fails, the application is migrated to another system within the same cluster. If the entire cluster fails, the application is migrated to a system in another cluster. Clustering on a global level also requires the replication of shared data to the remote site.