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Versions 11, 12 and Newer Databases: Fatal NI Connect Error 12170, 'TNS-12535: TNS:operation timed out' Reported in Alert Log (Doc ID 1286376.1)

Last updated on SEPTEMBER 01, 2023

Applies to:

Oracle Net Services - Version to [Release 11.1 to 12.2]
Oracle Database - Enterprise Edition - Version to [Release 19]
Information in this document applies to any platform.
TNS-12170, ORA-12170, TNS-12535, TNS-00505 alert.log


nt secondary err code: 110   Monitoring of the 11g database Alert log(s) may show frequent timeout related messages such as:

- On Oracle Solaris:



No changes are necessary, but may have recently upgraded the database to 11g release 1 or higher, or installed a new Oracle11g database.

Note: Prior to 11gR1 these same 'Fatal NI connect error 12170' are written to the sqlnet.log


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