How to fix the Oracle error ORA-28509: unable to establish a connection to non-Oracle system?

In this post, you’ll learn more about the Oracle ErrorORA-28509: unable to establish a connection to non-Oracle system with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-28509: unable to establish a connection to non-Oracle system

Reason for the Error ORA-28509: unable to establish a connection to non-Oracle system

Initialization of a database link to a non-Oracle system failed to connect to the Heterogeneous Services agent process for this non-Oracle system.

How to fix the Error ORA-28509: unable to establish a connection to non-Oracle system ?

You can fix this error in Oracle by following the below steps

Check the Net8 service name definition in the following places: — the USING clause of the CREATE DATABASE LINK statement — the TNSNAMES.ORA file — the Oracle Names Server The following are possible reasons for name mismatches: — The USING clause in the CREATE DATABASE LINK statement has to match the service name defined in the TNSNAMES.ORA file or in the Oracle Names Server. — The protocol-specific information in the service name definition must match the protocol-specific definition of the responding listener. — The SID= in the service name definition (in the TNSNAMES.ORA file or in Oracle Names Server) must match the value in the LISTENER.ORA file for the responding listener.