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TNS-12535/12606 and ORA-3136 on Connection to Database (Doc ID 2313573.1)

Last updated on APRIL 01, 2024

Applies to:

Oracle Net Services - Version to [Release 12.1 to 12.2]
Information in this document applies to any platform.


When trying to connect the database, client reporting the following Error:

ORA-28547: connection to server failed, probable Oracle Net admin error

The database alert log is reporting the error codes.

Fatal NI connect error 12170.

TNS for Linux: Version - Production
Oracle Bequeath NT Protocol Adapter for Linux: Version - Production
TCP/IP NT Protocol Adapter for Linux: Version - Production
Time: 30-SEP-2017 19:46:10
Tracing not turned on.
Tns error struct:
ns main err code: 12535

TNS-12535: TNS:operation timed out
ns secondary err code: 12606
nt main err code: 0
nt secondary err code: 0
nt OS err code: 0
Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=XXX.XXX.XXX.XXX)(PORT=50745))
Sat Sep 30 19:46:10 2017
WARNING: inbound connection timed out (ORA-3136)





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