HP Serviceguard Oracle DataGuard Toolkit User Guide, April 2011

NOTE: This configuration is supported both in single-instance and RAC environments. For better
understanding, the packages in the Figure 9 (page 16) are shown for a single-instance database.
Three data center configuration
Figure 10 Single-instance Data Guard setup in a Continentalclusters environment where the primary
cluster is configured as a Metrocluster
Figure 10 (page 17), describes a Continentalclusters setup with two clusters spread over three
different sites. The Primary Cluster is configured as a Metrocluster spread over two different sites
that are geographically dispersed within the confines of a metropolitan area. The Recovery Cluster
is configured on the third site as a Serviceguard cluster.
The primary database of Data Guard setup is configured as a Primary package in the Primary
Cluster (Metrocluster instance). The Primary Cluster has two data centers (sites), each of which
have a storage array for storing the data. Metrocluster enables data written to the primary site to
be replicated to the recovery site and hence the primary database instance can failover to any
node within the Primary Cluster.
The standby database is configured as a Data Receiver package in the Recovery Cluster. It will
receive the archived redo logs sent by the primary database instance irrespective of the node on
which the primary database is running. Cross subnet failover is allowed across the sites.
When the Primary Cluster fails, the user must run the cmrecovercl command to halt the Data
Receiver package and start the Recovery package. Once this command is run, the Recovery
package starts and brings up the Oracle database as a primary database. Thus there will be no
instance of a standby database running once the role of the database is changed to primary.
Multiple standby configurations are not supported within a Continentalclusters setup. However,
the ODG toolkit in Continentalclusters will not prevent customers from configuring standby databases
that are placed outside the Continentalclusters environment.
Supported configurations 17