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ORA-12516:

TNS:listener could not find available handler with matching protocol stack
Cause: None of the known and available service handlers for the given SERVICE_NAME support the client's protocol stack: transport, session, and presentation protocols.
Action: Check to make sure that the service handlers (e.g. dispatchers) for the given SERVICE_NAME are registered with the listener, are accepting connections, and that they are properly configured to support the desired protocols.
 SubjectReplies
1.[suse-oracle] ORA-125162