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Troubleshooting ORA-12547 TNS: Lost Contact (Doc ID 555565.1)

Last updated on MARCH 31, 2022

Applies to:

Oracle Database - Standard Edition - Version to [Release 10.2]
Oracle Database - Enterprise Edition - Version to [Release 12.1 to 12.2]
Oracle Net Services - Version to [Release 10.2 to 12.2]
Information in this document applies to any platform.


Aid in diagnosing and resolving the TNS-12547 or "lost contact" errors for both local and remote Oracle client connections.

Troubleshooting Steps

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In this Document
Troubleshooting Steps
 Bequeath (Local) :
 Remote Connections:
 Listener specific : 
 Diagnosis :

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