ORA-28040: No matching authentication protocol : Oracle 12c Upgrade

Question

We have migrated our Oracle database to 12c from 11g. We have a legacy application running in Java 1.5 and using ojdbc14.jar.

Our application is not able to create c

Answer 1

The main problem is that the JDBC thin client of the 10g uses the SHA-1 authentication protocol, this protocol is not allowed in the 12c, so it gives the error.

In my Oracle I could not find the sqlnet.ora file so I had to create it with the command:

vi $ORACLE_HOME/network/admin/sqlnet.ora

And I added the following:

SQLNET.ALLOWED_LOGON_VERSION=10
SQLNET.ALLOWED_LOGON_VERSION_CLIENT=10
SQLNET.ALLOWED_LOGON_VERSION_SERVER=10
SQLNET.ALLOWED_LOGON_VERSION=8
SQLNET.ALLOWED_LOGON_VERSION_CLIENT=8
SQLNET.ALLOWED_LOGON_VERSION_SERVER=8
SQLNET.AUTHENTICATION_SERVICES = (NONE)

So I had to stop and start the listener:

lsnrctl stop
lsnrctl start

Finally, I restart the database.

This should only be a workaround

Answer 2

I had a problem connecting to DB after migration to ORACLE 12c. The error was:java.sql.SQLException: ORA-28040: No matching authentication protocol. After setting this parametar SQLNET.ALLOWED_LOGON_VERSION=8 it was solved.

Thank you very much