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ORA-12514 and Slow Start of Managed Servers After a Database Failover (Doc ID 2793222.1)

Last updated on OCTOBER 31, 2022

Applies to:

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


When trying to start a managed server after a database failover, the following error is reported:
ORA-12514, TNS:listener does not currently know of service requested in connect descriptor

Fusion Middleware Infrastructure Domain ( configured in cluster mode with 4 Managed Server; each Managed Server is configured on dedicated hostnames.
The Infrastructure Domain has the Product and Business Schemas created in a 19c Database configured in an ACTIVE-STANDBY Topology:

  • Active Data Guard with FSFO (Fast-Start Failover Observer) and observer;
  • Oracle Multitenant architecture;
  • Oracle RAC capabilities.

In order to connect to the Database, for the Middleware and custom apps datasources, the below failover string is used, where the first scan is the primary database and the second scan is the standby:

With the primary database down and the standby running, the managed servers were unable to start.
If a manual database failover is executed, instead of isolating the RAC Database via networking and allowing the "observer" to initiate the failover, the managed server can be re-started. However, it takes 20 minutes for each managed server to start.
The issue occurs only when the RAC database is isolated from the network.




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