Using rdbms 11.2 as the repository for our Grid Control environmont, noticed a lot of the same errors in the alert file of the repository or/and the target database:

NI cryptographic checksum mismatch error: 12599.
TNS for Linux: Version – Production
Oracle Bequeath NT Protocol Adapter for Linux: Version – Production
TCP/IP NT Protocol Adapter for Linux: Version – Production
Time: 24-MAR-2011 11:58:31
Tracing not turned on.
Tns error struct:
ns main err code: 12599

TNS-12599: TNS:cryptographic checksum mismatch
ns secondary err code: 2526
nt main err code: 0
nt secondary err code: 0
nt OS err code: 0

Note: 1150874.1 gives the cause, workaround and solution:

Symptom: Login to 11g Oracle Enterprise Manager causes TNS-12599 error in the alert.log file in the 11.2 database OMS repository or target database.

Cause: The Enterprise Manager OMS connects to the 11.2 database using 10.2 JDBC Thin connection and AES256 encryption algorithm. The 11.2 DB does not support client JDBC connections using AES encryption.

Workaround:  on the the database side, put the following in sqlnet. ora:


No restart needed, no impact.
Patches for bug 9953045 and  bug 12360281 fix this problem.

– Bug 9953045   is to fix the issue for repository connection made from OMS (GC 11G REPOSITORY DB ALERT.LOG SHOWS TNS-12599)
– Bug 12360281 (applied to the OMS) is to fix target database connections made from OMS. When You may also need patch 6880880 (to overcome an Opatch problem.. )