In all replications, the source database must be an Oracle database. Therefore, two-way replication with MS SQL with SQL Server is not supported. ODBC connection is used to connect to MS SQL, thus to SQL Server, therefore System DSN (Data Source Name) with the same name must be setup created by the system administrator on both source and target systems.
If both source and target databases are running on Windows platform then DSN then System DSN (Data Source Name) with the same name are required on source and target machine. But if source is Linux then DNS System DSN is only required on Windows target machine.
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