HP Serviceguard Toolkits for Database Replication Solutions User Guide, March 2012

Figure 4 (page 10), shows a Data Guard configuration where the primary database is
configured as an RAC and the standby database is a single-instance database. Both primary
and standby databases are configured in separate Serviceguard clusters for high availability.
The RAC primary is combined with the ODG toolkit and the SGeRAC toolkit in a single
package. It is configured on Node 1 and Node 2 in the SG Cluster 1. The standby database
is configured as a single-instance Serviceguard failover package on Node 1 and Node 2 in
the SG Cluster 2. The standby database is combined with the ODG toolkit and the ECMT
Oracle toolkit in a single package. Data Guard replication takes place from RAC primary to
the single-instance standby database. These two clusters are independent, and packages
cannot failover across clusters.
3. Data Guard replication between RAC primary and RAC standby.
Figure 5 Data Guard replication between RAC primary and RAC standby
Figure 5 (page 11), shows a Data Guard configuration where both primary and standby
databases are configured in two different RAC setups. The RAC primary is configured on
nodes 1 and 2 of SG Cluster 1 and the RAC standby is configured on nodes 1 and 2 of SG
Cluster 2. These two clusters are not a part of a Continentalclusters. Data Guard replication
takes place between the RAC primary and the RAC standby.
NOTE: Configure these two clusters using the ODG toolkit in a Continentalclusters environment
to achieve automatic role management. For more information on how to configure clusters in
a Continentalclusters environment, see “Continentalclusters environment” (page 11).
In RAC standby, only one standby instance performs the task of applying the redo logs to the
database. This instance is known as the recovery instance and all other standby instances are
known as receiving instances. When the recovery instance fails, the method of restarting the
redo apply depends on whether the Data Guard Broker is configured. If the Broker is used,
the redo apply restarts automatically on the first available standby instance. If the Broker is
not used, the redo apply is restarted manually on one of the other standby instances.
Continentalclusters environment
A Continentalclusters configuration provides an alternative disaster recovery solution in which two
clusters are geographically dispersed. For information about setting up Continentalclusters, see
Designing Disaster Recovery HA Clusters Using Metrocluster and Continentalclusters Manual
available at http://www.hp.com/go/hpux-serviceguard-docs.
A typical Continentalclusters environment consists of a primary cluster (SG Cluster 1) and a recovery
cluster (SG Cluster 2). In the primary cluster, Data Guard is configured using the ODG toolkit while
the Oracle database is placed on a disk that is shared between the nodes in the primary cluster.
Supported configuration 11