ORA-28509: unable to establish a connection to non-Oracle system
Cause: Initialization of a database link to a non-Oracle system failed to connect to the Heterogeneous Services agent process for this non-Oracle system
Action: 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
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