Getting ORA-12516 Connecting To RAC Via LDAP Over JDBC (Doc ID 1489017.1)

Last updated on MAY 31, 2023

Applies to:

Symptoms

OID has been recently implemented, and it is having intermittent issues connecting to a RAC database.  
The error obtained is:

java.sql.SQLException: Listener refused the connection with the following error:
ORA-12516, TNS:listener could not find available handler with matching protocol stack

at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:412)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:531)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:221)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:503)
at oracle.jdbc.pool.OracleDataSource.getPhysicalConnection(OracleDataSource.java:280)
at oracle.jdbc.pool.OracleDataSource.getConnection(OracleDataSource.java:207)
at oracle.jdbc.pool.OracleDataSource.getConnection(OracleDataSource.java:157)
...
Caused by: oracle.net.ns.NetException: Listener refused the connection with the following error:
ORA-12516, TNS:listener could not find available handler with matching protocol stack
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:385)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1042)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:301)
... 8 more

There are no observed issues going through Oracle NET (ldap.ora); however, there is intermittent issue connecting via JDBC. If the SCAN IP Addresses are hardcoded in the ldap connection string, there is no issue. 

Changes

Cause

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