XADatasource and Oracle RAC - Load Balancing
JBoss 4.2.3 GA - Oracle 11g RAC
We have configured a XADatasource pointing to an Oracle RAC. When we get the connection from this datasource we do not obtain any load balancing, in other words every time we ask for a connection we obtain a connection to the same RAC node.
How can we configure the DS in order to have a load balancing on the RAC nodes?
Following the datasource configuration:
<jndi-name>jdbc/xxxxxxxx</jndi-name>
<track-connection-by-tx/>
<isSameRM-override-value>false</isSameRM-override-value>
<xa-datasource-class>oracle.jdbc.xa.client.OracleXADataSource</xa-datasource-class>
<xa-datasource-property name="URL">jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS=(protocol=tcp)(host=rac-scan)(port=xxx))(LOAD_BALANCE=YES)(CONNECT_DATA=(SERVE
R=DEDICATED)(SERVICE_NAME=dbname.domain)))</xa-datasource-property>
<xa-datasource-property name="User">XXXXXX</xa-datasource-property>
<xa-datasource-property name="Password">YYYYYY</xa-datasource-property>
<min-pool-size>0</min-pool-size>
<max-pool-size>60</max-pool-size>
<idle-timeout-minutes>2</idle-timeout-minutes>
<blocking-timeout-millis>30000</blocking-timeout-millis>
<!--sql to call when connection is created-->
<new-connection-sql>select 1 from dual</new-connection-sql>
<!--sql to call on an existing pooled connection when it is obtained from pool-->
<check-valid-connection-sql>select 1 from dual</check-valid-connection-sql>
<!-- Uses the pingDatabase method to check a connection is still valid before handing it out from the pool -->
<!--valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleValidConnectionChecker</valid-connection-checker-class-name-->
<!-- Checks the Oracle error codes and messages for fatal errors -->
<exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name>
<!-- Oracles XA datasource cannot reuse a connection outside a transaction once enlisted in a global transaction and vice-versa -->
<no-tx-separate-pools/>