11g and Newer: ORA-609 TNS-12537 and TNS-12547 or TNS-12170 in DB Alert.log

(Doc ID 1116960.1)

Last updated on JUNE 07, 2017

Applies to:

Oracle Net Services - Version to [Release 11.1 to 12.1]
Information in this document applies to any platform.
The issue documented here is limited in scope to 11g and newer instances.


The following errors are intermittently posted to the alert.log of an 11g database.

TNS-12547: TNS: Lost contact
ORA-609 Opiodr Aborting Process Unknown Ospid <nnnn>


TNS-12537: TNS: Connection closed
ORA-609 Opiodr Aborting Process Unknown Ospid

The ORA-609 might be accompanied by either the TNS-12537 or the TNS-12547 and might also include the following timeout messages:

Fatal NI connect error 12170.

TNS-12535: TNS:operation timed out

ns secondary err code: 12560

nt main err code: 505


This is likely a new installation of the 11g database.   The ORA-609 error code was introduced in 11g.  Also introduced in 11g is the ADR diagnostic method which results in TNS errors such as this to be thrown in the alert versus the sqlnet.log. 


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