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Resolving Problems with Connection Idle Timeout With Firewall (Doc ID 257650.1)

Last updated on JUNE 06, 2023

Applies to:

Oracle Net Services - Version and later
Information in this document applies to any platform.


This article describes connection idle time-out issues that occur because a firewall is configured to limit the time that a TCP connection can remain idle.
Very often in client -server environments, firewalls will abruptly terminate connections that appear idle when only one side is busy and there is no data on the wire.

This leads to any number of timeout errors such as TNS-12535, TNS-12170, ORA-3135, etc.
See also:  <Note: 1628949.1>  Alert Log Errors: 12170 TNS-12535/TNS-00505: Operation Timed Out


This article is  intended for Application/Database Administrators and Network Administrators who would like to understand and try to workaround connection "IDLE TIMEOUT" issues in a firewall or F5 load balancer environment.


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In this Document
 An Overview
Resolving problems with connection idle time-out

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