Hi
Hope you might have already gone through below, just in case if not. All of our developer tools/ETL tools datastage/Informatica etc. are failing with ora-28040 once we upgraded to oracle 12c.
This is due to, As per Oracle, In Oracle 12.1 the default value for the SQLNET.ALLOWED_LOGON_VERSION parameter has been updated to 11. This means that database clients using pre-11g JDBC thin drivers cannot authenticate to 12.1 database servers unless the SQLNET.ALLOWED_LOGON_VERSION parameter is set to the old default of 8.
Change/add the SQLNET.ALLOWED_LOGON_VERSION=8 in sqlnet.ora
Note: For the databases on AWS RDS this still works.
-Thanks
Suresh
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