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Troubleshooting ORA-3135 Connection Lost Contact (Doc ID 787354.1)

Last updated on SEPTEMBER 08, 2023

Applies to:

Oracle Net Services - Version and later
Oracle Database - Enterprise Edition - Version to [Release 11.2 to 12.2]
Oracle Database - Standard Edition - Version to [Release 19]
Information in this document applies to any platform.


Explains why a 3135 error is returned and helps to diagnose the underlying problem.

Troubleshooting Steps

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In this Document
Troubleshooting Steps
 (1) Transparent Application Failover (TAF)
 (2) Idle Connection Timeout
 (3) Firewall Manipulating  Sqlnet Data.
 (4) Data Required for Further Analysis

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