Only One ONS Registration Is Effective When Calling setONSConfiguration() Method

(Doc ID 460426.1)

Last updated on AUGUST 03, 2016

Applies to:

JDBC - Version 10.2.0 and later
Information in this document applies to any platform.


An application is using JDBC FCF (fast connection failover) against two RAC clusters. Each RAC cluster is composed of two nodes. For each RAC cluster, an implicit connection cache has been created. Also, for each RAC cluster, the related ONS nodes configuration is registered via the  setONSConfiguration() method.

To illustrate this, here is  the related sequence of code :

// ons configuration registration for rac cluster 1:
OracleDataSource rac1_ds = new OracleDataSource();
String ons_rac1_conf="nodes=node1:6201,node2:6201";

// ons configuration registration for rac cluster 2:
OracleDataSource rac2_ds = new OracleDataSource();
String ons_rac2_conf="nodes=node3:6201,node4:6201";

The problem is that  only the first ONS registration is taken into account by  the Oracle JDBC driver. Only the first ONS  configuration  (ons_rac1_conf="nodes=node1:6201,node2:6201"; ) will be effectively registered.
This can be verified (you might use the netstat command) by checking the different TCP connections to the RAC  cluster  nodes:  only TCP connections to  node1/port 6201 and node2/port 6201 are established.


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