Oracle Real Application Cluster (RAC) is a "share-everything" database architecture that
can provide high availability and load balancing. A typical configuration for an Oracle RAC contains
two or more Oracle RAC nodes that are clustered together and share the same storage.
About this task
This figure depicts a typical RAC physical topology in a cluster environment for the
application server, and both the failover and load balancing are enabled:
The application server cluster consists of two members: cluster-member1 and cluster-member2. The
Oracle RAC physical configuration contains two nodes: rac-node1 and rac-node2. The RAC nodes can be
located in the same physical machine with the cluster members, or they could be placed in entirely
different machines. The actual placement does not impact the fundamental qualities of the services
provided by RAC. To achieve both high availability and load-balancing, you can specify the Oracle
data source URL for both cluster members in the application server with the required
properties.
Procedure
- Navigate to the Oracle data source.
Click . If you don't already have an Oracle data source, create a new data source by
clicking New and completing the wizard. For the URL, substitute the
properties in the next step.
- Set the URL for the Oracle database with the required configuration parameters.
jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS_LIST=
(ADDRESS=(PROTOCOL=TCP)(HOST=rac-node1)(port=1521))
(ADDRESS=(PROTOCOL=TCP)(HOST=rac-node2)(port=1521)))
(FAILOVER=on)(LOAD_BALANCE=on)
(CONNECT_DATA=(SERVER=DEDICATED)
(SERVICE_NAME=<service_name>)))
Tip: Be aware of these configuration options:
- If you are not using Oracle services, then service_name will be the database
name in the example. If you are using Oracle services, then service_name will be
the name of the services.
- The example has FAILOVER and LOAD_BALANCE turned on. To turn one or both of these features off,
change on to off in the example.
- Click Apply or OK.