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Connections to Database Fail Reporting ORA-12547: TNS lost connection (Doc ID 1289174.1)

Last updated on FEBRUARY 18, 2020

Applies to:

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


Connections to the database, intermittently start to fail, reporting the error code ORA-12547: TNS lost connection.Upon checking the server, Netstat command shows many threads with a state of LISTENING  for local and Foreign address

Sockets are never released and a restart of the database free the resources.
ORA-12547 is a sympton of lack of sockets on the system
Setting SQLNET.EXPIRE_TIME does not help


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