VCS enables you to link clusters running at separate locations and switch service groups across clusters. Global clustering provides complete protection against failure of a cluster.
To understand how global clusters work, review the example of an Oracle RAC database configured using global clustering. Oracle RAC is installed and configured in cluster A and cluster B. Oracle data is located on shared disks within each cluster and is replicated across clusters to ensure data concurrency. The Oracle service groups are online on a node in cluster A and are configured to fail over on cluster A and cluster B.
Global clusters
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VCS continuously monitors and communicates events between clusters. Cluster-to-cluster communications ensures that the global cluster environment is aware of the state of global service group at all times.
In the event of a local node or application failure, the Oracle RAC service groups become available on other cluster nodes. If cluster A fails, the service groups can fail over to a remote cluster B. VCS also redirects clients when the application is online at the new location. For complete details on VCS global clusters:
See the Veritas Cluster Server User's Guide.