Database Error Messages

Release
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  • 23ai
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  • 19c
Updated
Jun 24, 2024

ORA-28547

connection to server failed, probable Oracle Net admin error

Cause

A failure occurred during initialization of a network connection from a client process to the Oracle server. The connection was completed but a disconnect occurred while trying to perform protocol-specific initialization, usually due to use of different network protocols by opposite sides of the connection. This usually is caused by incorrect Oracle Net administrative setup for database links or external procedure calls. The most frequent specific causes are: -- The connection uses a connect string which refers to a Heterogeneous Services agent instead of an Oracle server. -- The connection uses a connect string which includes an (HS=) specification. -- Hitting Ctrl+C before connection initialization is complete. -- Using DRCP on Windows with SQLNET.AUTHENTICATION_SERVICES set to NTS. -- Connection timeout due to SQLNET.INBOUND_CONNECT_TIMEOUT parameter when all shared servers are busy in shared server configuration. -- The character set of the database is not recognized by the client process, which may be caused by an incorrect or unnecessary setting of the ORA_NLS10 client environment variable or by a new or user-defined character set installed in the Oracle server and used for the database.


Action

Check Oracle Net administration in the following ways: -- When using TNSNAMES.ORA or an Oracle Names server, make sure that the client connection to the Oracle server uses the correct service name or SID. -- Check LISTENER.ORA on the connection end point's host machine to assure that this service name or SID refers to the correct server. -- Confirm in TNSNAMES.ORA or the equivalent service definition that the connect string does not contain (HS=). -- Set SQLNET.AUTHENTICATION_SERVICES to NONE when using DRCP on Windows. -- Verify the NLS configuration of the Oracle client process. Ensure that the database character set is supported by the Oracle client software. If necessary, upgrade the Oracle client software or install the missing user-defined character set.