Oracle : Ошибка ORA-03136

"inbound connection timed out"
*Cause: Inbound connection was timed out by the server because
user authentication was not completed within the given time
specified by SQLNET.INBOUND_CONNECT_TIMEOUT or its default value
*Action: 1) Check SQL*NET and RDBMS log for trace of suspicious connections.
2) Configure SQL*NET with a proper inbound connect timeout value
if necessary.

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