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ORA-12518 / TNS-12518 Troubleshooting (Doc ID 556428.1)

Last updated on DECEMBER 11, 2019

Applies to:

Oracle Net Services - Version to [Release 11.2 to 12.2]
Information in this document applies to any platform.


Connexion fails with the error : TNS-12518: TNS:listener could not hand off client connection

One of the following errors could also appear :

ORA-12547 / TNS-12547: lost contact
ORA-12537 / TNS-12537: connection closed
ORA-3135   / TNS-3135  : connection lost contact
ORA-3113   / TNS-3113  : end-of-file on communication channel
ORA-3106   / TNS-3106  : fatal two-task communication protocol error
ORA -3136 / TNS-3136   : WARNING inbound connection timed out
ORA-12535 / TNS-12535: TNS:operation timed out
ORA-12170 / TNS-12170: Connect timeout occurred
ORA-12637 / TNS-12637: Text: Packet receive failed


memory consumption and/or high load


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